I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

The earliest databook entry I see for the 5963 is 1956 (Sylvania). The
earliest example I have with clear date code is 1959 production
Stromberg-Carlson. Some older usenet posts indicate that RCA continued
production up through the mid-late-Lasnerian 80's (this is roughly the
same time frame through which Philips etc. continued producing
12AU7's).

If you have tubes or tube boxes with date codes, I'm interested in
trying to match up manufacturer/brand with various production dates.
Like all tubes it's possible that sometimes the brand name the tube was
sold under is unrelated to the actual manufacturer (although I
generally associate this practice with crappy consumer tubes I'm sure
it also happened with some industrial types.)

If there are E. Europe/Russian/Chinese tubes being sold as 5963's
today, I am generally NOT interested in these.

Tim.

wrote:

I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

I.E. the cure for "sleeping sickness". Inimical to flip-flops.


The earliest databook entry I see for the 5963 is 1956 (Sylvania). The
earliest example I have with clear date code is 1959 production
Stromberg-Carlson. Some older usenet posts indicate that RCA continued
production up through the mid-late-Lasnerian 80's (this is roughly the
same time frame through which Philips etc. continued producing
12AU7's).

I know I used them heavily in the '53 to '57 era. About 10 years
ago I discovered my wife had thrown out my vacuum tube collection,
along with a tube tester. I had plenty of them, in original
cartons, along with such things as the 224a and UV199, even 201A
with bayonet sockets!

--
"If you want to post a followup via groups.google.com, don't use
the broken "Reply" link at the bottom of the article. Click on
"show options" at the top of the article, then click on the
"Reply" at the bottom of the article headers." - Keith Thompson
More details at: http://cfaj.freeshell.org/google/
Also see http://www.safalra.com/special/googlegroupsreply/

On 14 May 2006 07:25:04 -0700,
wrote:
I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

The earliest databook entry I see for the 5963 is 1956 (Sylvania). The
earliest example I have with clear date code is 1959 production
Stromberg-Carlson. Some older usenet posts indicate that RCA continued
production up through the mid-late-Lasnerian 80's (this is roughly the
same time frame through which Philips etc. continued producing
12AU7's).

My valve (tube) data book from 1970 lists them as "Osbolete" by that
date. Also manufactured, or re-badged, in the UK by Brimar, apparently.

I have a couple of cds full of old valve/tube manufacturers data somewhere,
if I can lay my hands on them I'll take a look and let you know what I find.

--
Cheers,
Stan Barr stanb .at. dial .dot. pipex .dot. com
(Remove any digits from the addresses when mailing me.)

The future was never like this!

wrote in message
ups.com...
I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

snip

Though I don't know when they were first manufactured...
that tube sure brings up some good memories.
In the early to mid 1960's they were often avail used at very low prices
and we'd use them in our ham radio modulators as the first stage.
They worked great.
Supposedly they were pulled from IBM mainframes after so many hours...
but they still had plenty of life left in them. To this day I still have a
few of them left

wrote:

wrote:
The earliest databook entry I see for the 5963 is 1956 (Sylvania).

Poking around through the shelves last night, I also found it listed in
the 1951 ARRL handbook.

The highest-numbered 59xx series industrial tube in that edition was
5964, so assuming:

1. The 59xx numbers were assigned sequentially
2. The ARRL handbook lags a year or so behind product announcement

then the beginning of production for the 5963 might be 1949 or 1950.

I also found some HP-labeled 5963's that I probably stripped from HP
decimal counter modules 30 years ago. No apparent date codes. I'm
guessing that HP was relabeling somebody else's tubes.

Tim.


When you used as many tubes as HP was at the time the manufacturers
were more than happy to put the HP logo on the tubes at the factory.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

wrote in message
oups.com...
wrote:
The earliest databook entry I see for the 5963 is 1956 (Sylvania).

Poking around through the shelves last night, I also found it listed in
the 1951 ARRL handbook.

The highest-numbered 59xx series industrial tube in that edition was
5964, so assuming:

1. The 59xx numbers were assigned sequentially
2. The ARRL handbook lags a year or so behind product announcement

then the beginning of production for the 5963 might be 1949 or 1950.


FWIW: I found no listing for the 5963 in my 1949 ARRL handbook


5693 was the last "5000" series listing that year

wrote:

I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

There was a PC motherboard made by A-open that had a tube on it, for the
sound card circuit audio output. Might be one of the above computer
grade triodes.... :-)

"Michael A. Terrell" wrote:
wrote:

.... snip ...

I also found some HP-labeled 5963's that I probably stripped from
HP decimal counter modules 30 years ago. No apparent date codes.
I'm guessing that HP was relabeling somebody else's tubes.

When you used as many tubes as HP was at the time the manufacturers
were more than happy to put the HP logo on the tubes at the factory.

I seem to recall that 5963s and the ilk cost us about 10 cents each
in the late '50s.

--
"If you want to post a followup via groups.google.com, don't use
the broken "Reply" link at the bottom of the article. Click on
"show options" at the top of the article, then click on the
"Reply" at the bottom of the article headers." - Keith Thompson
More details at: http://cfaj.freeshell.org/google/
Also see http://www.safalra.com/special/googlegroupsreply/

robert casey wrote:
wrote:

I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
They very often show up on the surplus market both NIB and in decade
counter assemblies used by military/telecom/test equipment.

There was a PC motherboard made by A-open that had a tube on it, for the
sound card circuit audio output. Might be one of the above computer
grade triodes.... :-)

I believe that in at least one of the "tube on a motherboard" cases
there was a minor scandal (shocked! shocked I tell you!) when it was
revealed that the bulk of the nice orange glow coming from the tube was
actually provided by a couple of orange LED's mounted behind the tube
:-).

Of course most 12AU7-type dual triodes have indirectly heated cathodes
and not much light from the filament is visible.

In my case, I'm much more interested in 40's/50's/60's vintage tubes
intended for low- and medium-level digital/switching use. (e.g. I'm not
all that interested in heavy industrial switching tubes like thyratrons
at the moment, but I am interested in tubes like the 5963's that were
used for low-level switching logic and computer use.)

Tim.

In article ,
says...
wrote:

wrote:
The earliest databook entry I see for the 5963 is 1956 (Sylvania).

Poking around through the shelves last night, I also found it listed in
the 1951 ARRL handbook.

The highest-numbered 59xx series industrial tube in that edition was
5964, so assuming:

1. The 59xx numbers were assigned sequentially
2. The ARRL handbook lags a year or so behind product announcement

then the beginning of production for the 5963 might be 1949 or 1950.

I also found some HP-labeled 5963's that I probably stripped from HP
decimal counter modules 30 years ago. No apparent date codes. I'm
guessing that HP was relabeling somebody else's tubes.

Tim.


When you used as many tubes as HP was at the time the manufacturers
were more than happy to put the HP logo on the tubes at the factory.

In the '60s, so the folklore goes, a woman in Poughkeepsie NY
called TJ Jr's office demanding that someone come out and fix her
TV set. She had just paid big bucks to have it fixed and it was
out again. No explanation would convince her that IBM didn't make
TV sets nor service them. Finally they sent someone out just as a
PR measure. Yep, the service guy had used IBM branded tubes to fix
her set. She was adamant that IBM fix their problem. They did,
then went looking for the moonlighting service tech. ;-)

--
Keith

On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff. snip

"Sleeping sickness," which also happens when B+ is applied with no
filament.

I used a ton of 5963s in various applications, wherever there was a
need for long period hold-off. I had an Exact waveform synthesizer
that had 156 of 'em in the box! My own tests showed that a 5963 would
survive in that application well, while any analog circuit tube
variant of the 12AU7 would die off in short order if exposed to long
period cut-off.

The first time I saw the 5963 in an RCA catalog was 1956, and they
were marketed for VT digital computers, mostly, such as the UNIVAC.
NORAD used these by the boxcar full in their early UNIVACs that were
used in the NORAD system in the '50s through the '70s. Many of the
used 5963s on the market now are probably part-outs from the old NORAD
machines, which would occupy large buildings and need 100s of tons of
refrigeration to cool.

5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.

On 15 May 2006 03:35:04 -0700, wrote:

I also found some HP-labeled 5963's that I probably stripped from HP
decimal counter modules 30 years ago. No apparent date codes. I'm
guessing that HP was relabeling somebody else's tubes. snip

H-P usually used OEM branded RCAs, although some Sylvania "red tops"
have shown up in H-P dress here and there.

NudoKiller wrote:
On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.
....
5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.

Cool.. sounds like an ideal candidate for a guitar amp
stage to add some color to the sound! Warren.

In article ,
wrote:

On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.

5963's are computer-grade dual triodes, similar to 12AU7's but with
cathodes designed to not lose emission when the tube is held in cutoff.
snip

"Sleeping sickness," which also happens when B+ is applied with no
filament.

Bob, are you sure "Sleeping sickness" also occurs when B+ is applied
without "filament" power? I never heard of that before, although that
clearly doesn't mean it doesn't happen. Considering that this effect is
not often spoken about, a reference explaining the mechanism would be nice
to have? There has been plenty written about the garden variety of
"Sleeping sickness", it is strange that little has apparently been written
about this problem. If the effect does actually exist, does it affect the
cathode in the same way as the "Sleeping sickness" caused by extended
cutoff, or might it be related to the so called "cathode striping" non
problem that audiophools worry so much about?

I used a ton of 5963s in various applications, wherever there was a
need for long period hold-off. I had an Exact waveform synthesizer
that had 156 of 'em in the box! My own tests showed that a 5963 would
survive in that application well, while any analog circuit tube
variant of the 12AU7 would die off in short order if exposed to long
period cut-off.

The first time I saw the 5963 in an RCA catalog was 1956,

Interesting, you must have been a precocious reader, I thought you were
just born some time around 1956?

and they
were marketed for VT digital computers, mostly, such as the UNIVAC.
NORAD used these by the boxcar full in their early UNIVACs that were
used in the NORAD system in the '50s through the '70s.

Are you sure the NORAD computers were built by UNIVAC, I thought IBM built
the large building sized NORAD computers?

Many of the
used 5963s on the market now are probably part-outs from the old NORAD
machines, which would occupy large buildings and need 100s of tons of
refrigeration to cool.

5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.

That's good to know, it's probably why audiophools like the computer tubes.


Regards,

John Byrns


Surf my web pages at, http://users.rcn.com/jbyrns/

On Tue, 16 May 2006 16:24:18 -0400, "Warren W. Gay"
wrote:

NudoKiller wrote:
On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.
...
5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.

Cool.. sounds like an ideal candidate for a guitar amp
stage to add some color to the sound! Warren. snip

It doesn't quite work that way. The non-linearity causes some pretty
awful third harmonic garbage. I use 5963 as relay drivers in Leslie
organ speakers, where they work forever. Changing one over to the
voltage stage driving the 6550s creates aural havoc. Since most
gee-tawr fans are deaf, maybe it'd sound good to them! I've also
noted a tendency toward low Gm on 5963s vis à vis 12AU7s and their
industrial AF/RF counterparts, like the 5814 and 6003.

On Tue, 16 May 2006 16:34:51 -0500, (John Byrns) wrote:

Bob, are you sure "Sleeping sickness" also occurs when B+ is applied
without "filament" power? I never heard of that before, although that
clearly doesn't mean it doesn't happen. snip

Yes, it does! I witnessed this happen one time which resulted in an
supervisor earning a little unpaid vacation time.

Old multiplex equipment associated with Types J, K and L carrier
systems used by AT&T's various companies built in the '40s and '50s
used basically two tubes...the 311B triode, and the 310A sharp cutoff
pentode, essentially a five prong, 5 V filament 6C6, for anything
below the mastergroup MUX level. Above that, the 404A (basically a 5V
6AK5) and the 417A single triode were used for mastergroup gain and
stacking. One day, a migration to IC-based equipment on another floor
occurred in our office, the largest carrier office in the US,
rendering an entire floor's worth of antique channel modems, group
demods, supergroup demods and all associated equipment such as carrier
supplies to be relegated to "spare" status. A transmission man
working that floor, trying to earn a few "brownie" points,
disconnected all the -24V filament battery at the BDFB to all this
gear. Laziness and timidity precluded him from removing the +130 and
+315 plate supplies. Thus, over 750 311B and 310A tubes were left in
situ with their usual B+ on the plates and cold filaments.

About three months later, a surge in traffic demand prompted the
circuit provision bureau to reassign new multiplex facilities to this
equipment, and within a short lead time. When such work happens, the
"circuit order" worker tests the gear both directions, sets levels as
appropriate and checks for basic transmission impediments. In this
case, the equipment didn't pass tone anywhere and wouldn't mod or
demod anything at all, and a trip to the BDFB found boxes of 1 1/3 amp
grasshopper fuses all placed neatly on the floor in front of the fuse
bay. After replacing all the filament supply fuses, the equipment
still failed, but some of it would pass modulated/demodulated signal,
but at bad levels and with not nearly enough gain to meet
specifications. After some checking, they called me down to try to
figure what happened.

Western Electric gear from that era used an "in service" tube test
regimen that looked basically at plate and filament current and
"filament activity" (an old term that really meant "cathode activity"
in anything other than direct heated tubes.) The in service tests
showed acceptable filament current, but the plate current was either
gone or very weak. In cases where there was at least some plate
current, dropping the filament current 10% wouldn't cause a dip in the
plate current...odd. A trip to the Hickok Cardmatic (KS version, of
course) showed all the tubes on the entire floor to be "dead" for Gm.
That's when the "brownie" said, "Oh...well, I took all the filament
fuses out of everything to save power. I reported it to my boss, and
he put an attaboy in my folder." A little investigation proved this
to be true, and the supervisor was given some time off for being an
idiot. A look at the Bell System Practices relating to vacuum tubes
specifically stated that at no time should any tube of any
configuration, except for cold cathode tubes, be allowed to stand with
B+ on any element without the filament being hot.

Some further investigation with the folks at the Littleton, CO WECO
tube plant confirmed that running any tube with the plates energized
and no filament will cause the same, or worse, symptoms as "sleeping
sickness" generally attributed to having a tube run in cutoff for long
periods of time. In short, what happens in either case of "sleeping
sickness" is that the plate winds up acting as a getter, thus becoming
unreceptive to electron reception from the cathode after being plated
with contaminents within the envelope. That explained immediately why
the tubes, while testing bad for Gm, tested good for cathode activity.
This was further confirmed by the fact that newer tubes were still at
least conducting something, while tubes that were some 30-40 years old
were completely dead on test, although the records showed their last
"in service" current test to be well within specs. Conversations with
retiring engineers at the tube plant confirmed that no "real life"
vacuum tube had a very good vacuum in it, and even if it had one, it
would be partially destroyed during the initial aging process by
gasification of the tungsten on the filament and thorium from the hot
plates. That's why tubes have getters in them, after all. As the
fellow told me, "You cut off electron flow, and that plate makes a
really attractive getter...the higher the B+, the more it "gets!" Add
to this that the cathode, grids and filaments are all at or near
ground potential, and you see how this can happen to the plates.

In the final tally for this goof, over 350 310A tubes, at $150 a pop,
and 200 some odd 311Bs, at $75 a pop, had to be replaced on an
emergency basis. At the time, Western Electric was getting out of
tube manufacturing altogether, and the assembly and aging lines for
the old ST envelope tubes were out of commission while the equipment
was being sold to Richardson Electronics. As it turned out, a canvass
of toll offices across the country had to be done to mine every
available 310A and 311B, even old "pulls" from retired equipment, to
get the MUX gear back into service. As it was, the due date for the
facility additions was jeopardized by over two months, and the carrier
group responsible for the gear (ours) had to buy all new Richardson
tubes for the offices which gave up their spares. Total cost of the
fiasco: over $130,000. There was little solace in the fact that the
removal of the filament battery saved about $500 in power costs. To
add insult to injury, the equipment only carried the service for
another six months before being finally retired and scrapped.

"Audiophools" worrying about "cathode stripping" has nothing whatever
to do with "sleeping sickness." I've yet to see any "audiophool" who
actually knows how a tube works, anyway. You have to expect this from
people who refer to audio phenomina as "air," "stage," "detail,"
"crispness" and other assorted laughable terms.

dB

Sidebar: On that particular floor resided many old pieces of gear
from the 1930s, including bays of voice order wire equipment
associated with long gone J and K carrier systems. In them were rows
of bayonet based 101D triodes and 201As, most dating from the 1930s,
some from the '40s. All tested good when pulled after 45+ years of
continuous service. I shudder to think what these old things would've
brought today on fraudBay. The secret to long tube life at the phone
company? Running filaments 10% below rated voltage and excellent
quality elements. The Richardson replacements which came later were
nowhere near the quality of any old WECO tube, and WECO tubes made in
the early '80s were almost as bad.

In article ,
(NudoKiller) writes:

On Tue, 16 May 2006 16:24:18 -0400, "Warren W. Gay"
wrote:

NudoKiller wrote:

On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.
...
5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.

Cool.. sounds like an ideal candidate for a guitar amp
stage to add some color to the sound! Warren. snip

It doesn't quite work that way. The non-linearity causes some pretty
awful third harmonic garbage.

IMHO a lot of electronic music is full of awful third-harmonic garbage.
Perhaps Warren is on to something. Either that, or my old-fashioned
analog ears are acting up again.

--
/~\ lid (Charlie Gibbs)
\ / I'm really at ac.dekanfrus if you read it the right way.
X Top-posted messages will probably be ignored. See RFC1855.
/ \ HTML will DEFINITELY be ignored. Join the ASCII ribbon campaign!

wrote:

The earliest databook entry I see for the 5963 is 1956 (Sylvania). The
earliest example I have with clear date code is 1959 production
Stromberg-Carlson. Some older usenet posts indicate that RCA continued
production up through the mid-late-Lasnerian 80's (this is roughly the
same time frame through which Philips etc. continued producing
12AU7's).

Shame on you for not owning a copy of Tube Lore.

5963 was registered on 7-5-1950.

Like many early "computer" tubes, the original application was in IFF
gear, mostly for the SIF encoders and decoders.

Will

"DeserTBoB" wrote in message ...
On Tue, 16 May 2006 16:34:51 -0500, (John Byrns) wrote:

Bob, are you sure "Sleeping sickness" also occurs when B+ is applied
without "filament" power? I never heard of that before, although that
clearly doesn't mean it doesn't happen. snip

Yes, it does! I witnessed this happen one time which resulted in an
supervisor earning a little unpaid vacation time.

Old multiplex equipment associated with Types J, K and L carrier
systems used by AT&T's various companies built in the '40s and '50s
used basically two tubes...the 311B triode, and the 310A sharp cutoff
pentode, essentially a five prong, 5 V filament 6C6, for anything
below the mastergroup MUX level. Above that, the 404A (basically a 5V
6AK5) and the 417A single triode were used for mastergroup gain and
stacking. One day, a migration to IC-based equipment on another floor
occurred in our office, the largest carrier office in the US,
rendering an entire floor's worth of antique channel modems, group
demods, supergroup demods and all associated equipment such as carrier
supplies to be relegated to "spare" status. A transmission man
working that floor, trying to earn a few "brownie" points,
disconnected all the -24V filament battery at the BDFB to all this
gear. Laziness and timidity precluded him from removing the +130 and
+315 plate supplies. Thus, over 750 311B and 310A tubes were left in
situ with their usual B+ on the plates and cold filaments.

About three months later, a surge in traffic demand prompted the
circuit provision bureau to reassign new multiplex facilities to this
equipment, and within a short lead time. When such work happens, the
"circuit order" worker tests the gear both directions, sets levels as
appropriate and checks for basic transmission impediments. In this
case, the equipment didn't pass tone anywhere and wouldn't mod or
demod anything at all, and a trip to the BDFB found boxes of 1 1/3 amp
grasshopper fuses all placed neatly on the floor in front of the fuse
bay. After replacing all the filament supply fuses, the equipment
still failed, but some of it would pass modulated/demodulated signal,
but at bad levels and with not nearly enough gain to meet
specifications. After some checking, they called me down to try to
figure what happened.

Western Electric gear from that era used an "in service" tube test
regimen that looked basically at plate and filament current and
"filament activity" (an old term that really meant "cathode activity"
in anything other than direct heated tubes.) The in service tests
showed acceptable filament current, but the plate current was either
gone or very weak. In cases where there was at least some plate
current, dropping the filament current 10% wouldn't cause a dip in the
plate current...odd. A trip to the Hickok Cardmatic (KS version, of
course) showed all the tubes on the entire floor to be "dead" for Gm.
That's when the "brownie" said, "Oh...well, I took all the filament
fuses out of everything to save power. I reported it to my boss, and
he put an attaboy in my folder." A little investigation proved this
to be true, and the supervisor was given some time off for being an
idiot. A look at the Bell System Practices relating to vacuum tubes
specifically stated that at no time should any tube of any
configuration, except for cold cathode tubes, be allowed to stand with
B+ on any element without the filament being hot.

Some further investigation with the folks at the Littleton, CO WECO
tube plant confirmed that running any tube with the plates energized
and no filament will cause the same, or worse, symptoms as "sleeping
sickness" generally attributed to having a tube run in cutoff for long
periods of time. In short, what happens in either case of "sleeping
sickness" is that the plate winds up acting as a getter, thus becoming
unreceptive to electron reception from the cathode after being plated
with contaminents within the envelope. That explained immediately why
the tubes, while testing bad for Gm, tested good for cathode activity.
This was further confirmed by the fact that newer tubes were still at
least conducting something, while tubes that were some 30-40 years old
were completely dead on test, although the records showed their last
"in service" current test to be well within specs. Conversations with
retiring engineers at the tube plant confirmed that no "real life"
vacuum tube had a very good vacuum in it, and even if it had one, it
would be partially destroyed during the initial aging process by
gasification of the tungsten on the filament and thorium from the hot
plates. That's why tubes have getters in them, after all. As the
fellow told me, "You cut off electron flow, and that plate makes a
really attractive getter...the higher the B+, the more it "gets!" Add
to this that the cathode, grids and filaments are all at or near
ground potential, and you see how this can happen to the plates.

In the final tally for this goof, over 350 310A tubes, at $150 a pop,
and 200 some odd 311Bs, at $75 a pop, had to be replaced on an
emergency basis. At the time, Western Electric was getting out of
tube manufacturing altogether, and the assembly and aging lines for
the old ST envelope tubes were out of commission while the equipment
was being sold to Richardson Electronics. As it turned out, a canvass
of toll offices across the country had to be done to mine every
available 310A and 311B, even old "pulls" from retired equipment, to
get the MUX gear back into service. As it was, the due date for the
facility additions was jeopardized by over two months, and the carrier
group responsible for the gear (ours) had to buy all new Richardson
tubes for the offices which gave up their spares. Total cost of the
fiasco: over $130,000. There was little solace in the fact that the
removal of the filament battery saved about $500 in power costs. To
add insult to injury, the equipment only carried the service for
another six months before being finally retired and scrapped.

"Audiophools" worrying about "cathode stripping" has nothing whatever
to do with "sleeping sickness." I've yet to see any "audiophool" who
actually knows how a tube works, anyway. You have to expect this from
people who refer to audio phenomina as "air," "stage," "detail,"
"crispness" and other assorted laughable terms.

Thanks for relating the most persuasive example I've ever read of this
obscure phenomenon. I'm sure many of us envy your experience with the
real WE tubes and equipment (I certainly do).

But Gee, dB, I know how a tube works, and I also know the meaning of
"air", "stage", "detail", "crispness" and other assorted terms used by audio
professionals to describe what one hears when critically listening to a
sound system. They are more useful and descriptive than, "That sounds
good", or "That stinks".

If you find these audio terms laughable, how do you deal with the Latin
terms your doctors toss around? Does the term, "squamas cell carcinoma"
cause you to roll on the floor, laughing your ass off? I mean, that gibberish
couldn't possibly mean anything real, right?

sigh

Enjoy your life, dB. Get lots of "air" - air is good. And don't get "squamas
cell carcinoma" - carcinoma is bad, whether you understand the terminology
or not.

Fred

dB

Sidebar: On that particular floor resided many old pieces of gear
from the 1930s, including bays of voice order wire equipment
associated with long gone J and K carrier systems. In them were rows
of bayonet based 101D triodes and 201As, most dating from the 1930s,
some from the '40s. All tested good when pulled after 45+ years of
continuous service. I shudder to think what these old things would've
brought today on fraudBay. The secret to long tube life at the phone
company? Running filaments 10% below rated voltage and excellent
quality elements. The Richardson replacements which came later were
nowhere near the quality of any old WECO tube, and WECO tubes made in
the early '80s were almost as bad.

wrote:
wrote:

The earliest databook entry I see for the 5963 is 1956 (Sylvania). The
earliest example I have with clear date code is 1959 production
Stromberg-Carlson. Some older usenet posts indicate that RCA continued
production up through the mid-late-Lasnerian 80's (this is roughly the
same time frame through which Philips etc. continued producing
12AU7's).

Shame on you for not owning a copy of Tube Lore.

5963 was registered on 7-5-1950.

Like many early "computer" tubes, the original application was in IFF
gear, mostly for the SIF encoders and decoders.

My only excuse is that my copy of Tube Lore is on order and hasn't
arrived yet :-). If Ludwell Sibley's publications were available
electronically (e.g. indexed by Google) I would have a far easier time
searching out this stuff. As it is, my references consist largely of
50's and 60's era electronics books and catalogs, some of which I
haven't really looked through in 20 or 30 years (if ever!). I have a
very little bit of pre-war literature and books.

I'm guessing that the 5xxx industrial tubes were mostly registered in
numerical order. But does the book give much guidance on who produced
these tubes and when, who relabeled them, and when they stopped being
produced?

I'm 90% certain that my 1959-date-code Stromberg Carlsons were actually
made by Sylvania, just by physical comparison. And I'm pretty sure that
my un-date-coded HP 5963's were made by RCA, probably in the very late
50's or very early 60's. Does Mr. Sibley's book provide any guidance in
this area?

Tim.

Charlie Gibbs wrote:
In article ,
(NudoKiller) writes:

On Tue, 16 May 2006 16:24:18 -0400, "Warren W. Gay"
wrote:

NudoKiller wrote:

On 14 May 2006 07:25:04 -0700, wrote:

I'm trying to research the range of years over which 5963's were
produced.
...
5963s are NOT good tubes for audio or RF, I've found. Their curve,
while good for switch and flip-flop applications, is curiously
non-linear in the middle.
Cool.. sounds like an ideal candidate for a guitar amp
stage to add some color to the sound! Warren. snip
It doesn't quite work that way. The non-linearity causes some pretty
awful third harmonic garbage.

IMHO a lot of electronic music is full of awful third-harmonic garbage.
Perhaps Warren is on to something. Either that, or my old-fashioned
analog ears are acting up again.

A lot of guitar amp work is done to create the right kind
of distortion. 3rd order hamonics are ok, as long as the
energy isn't all there (you also want a fairly even distribution
of other harmonics, obviously tapering off at the upper end).
I'll have acquire a few of these babies and try them in the
preamp I built a while ago.

Warren.

"Ft.peoplepc.com" wrote in
news

"DeserTBoB" wrote in message
...
On Tue, 16 May 2006 16:34:51 -0500, (John Byrns)
wrote:

Bob, are you sure "Sleeping sickness" also occurs when B+ is applied
without "filament" power? I never heard of that before, although
that clearly doesn't mean it doesn't happen. snip

Yes, it does! I witnessed this happen one time which resulted in an
supervisor earning a little unpaid vacation time.

Old multiplex equipment associated with Types J, K and L carrier
systems used by AT&T's various companies built in the '40s and '50s
used basically two tubes...the 311B triode, and the 310A sharp cutoff
pentode, essentially a five prong, 5 V filament 6C6, for anything
below the mastergroup MUX level. Above that, the 404A (basically a
5V 6AK5) and the 417A single triode were used for mastergroup gain
and stacking. One day, a migration to IC-based equipment on another
floor occurred in our office, the largest carrier office in the US,
rendering an entire floor's worth of antique channel modems, group
demods, supergroup demods and all associated equipment such as
carrier supplies to be relegated to "spare" status. A transmission
man working that floor, trying to earn a few "brownie" points,
disconnected all the -24V filament battery at the BDFB to all this
gear. Laziness and timidity precluded him from removing the +130
and +315 plate supplies. Thus, over 750 311B and 310A tubes were
left in situ with their usual B+ on the plates and cold filaments.

About three months later, a surge in traffic demand prompted the
circuit provision bureau to reassign new multiplex facilities to this
equipment, and within a short lead time. When such work happens, the
"circuit order" worker tests the gear both directions, sets levels as
appropriate and checks for basic transmission impediments. In this
case, the equipment didn't pass tone anywhere and wouldn't mod or
demod anything at all, and a trip to the BDFB found boxes of 1 1/3
amp grasshopper fuses all placed neatly on the floor in front of the
fuse bay. After replacing all the filament supply fuses, the
equipment still failed, but some of it would pass
modulated/demodulated signal, but at bad levels and with not nearly
enough gain to meet specifications. After some checking, they called
me down to try to figure what happened.

Western Electric gear from that era used an "in service" tube test
regimen that looked basically at plate and filament current and
"filament activity" (an old term that really meant "cathode activity"
in anything other than direct heated tubes.) The in service tests
showed acceptable filament current, but the plate current was either
gone or very weak. In cases where there was at least some plate
current, dropping the filament current 10% wouldn't cause a dip in
the plate current...odd. A trip to the Hickok Cardmatic (KS version,
of course) showed all the tubes on the entire floor to be "dead" for
Gm. That's when the "brownie" said, "Oh...well, I took all the
filament fuses out of everything to save power. I reported it to my
boss, and he put an attaboy in my folder." A little investigation
proved this to be true, and the supervisor was given some time off
for being an idiot. A look at the Bell System Practices relating to
vacuum tubes specifically stated that at no time should any tube of
any configuration, except for cold cathode tubes, be allowed to stand
with B+ on any element without the filament being hot.

Some further investigation with the folks at the Littleton, CO WECO
tube plant confirmed that running any tube with the plates energized
and no filament will cause the same, or worse, symptoms as "sleeping
sickness" generally attributed to having a tube run in cutoff for
long periods of time. In short, what happens in either case of
"sleeping sickness" is that the plate winds up acting as a getter,
thus becoming unreceptive to electron reception from the cathode
after being plated with contaminents within the envelope. That
explained immediately why the tubes, while testing bad for Gm, tested
good for cathode activity. This was further confirmed by the fact
that newer tubes were still at least conducting something, while
tubes that were some 30-40 years old were completely dead on test,
although the records showed their last "in service" current test to
be well within specs. Conversations with retiring engineers at the
tube plant confirmed that no "real life" vacuum tube had a very good
vacuum in it, and even if it had one, it would be partially destroyed
during the initial aging process by gasification of the tungsten on
the filament and thorium from the hot plates. That's why tubes have
getters in them, after all. As the fellow told me, "You cut off
electron flow, and that plate makes a really attractive getter...the
higher the B+, the more it "gets!" Add to this that the cathode,
grids and filaments are all at or near ground potential, and you see
how this can happen to the plates.

In the final tally for this goof, over 350 310A tubes, at $150 a pop,
and 200 some odd 311Bs, at $75 a pop, had to be replaced on an
emergency basis. At the time, Western Electric was getting out of
tube manufacturing altogether, and the assembly and aging lines for
the old ST envelope tubes were out of commission while the equipment
was being sold to Richardson Electronics. As it turned out, a
canvass of toll offices across the country had to be done to mine
every available 310A and 311B, even old "pulls" from retired
equipment, to get the MUX gear back into service. As it was, the
due date for the facility additions was jeopardized by over two
months, and the carrier group responsible for the gear (ours) had to
buy all new Richardson tubes for the offices which gave up their
spares. Total cost of the fiasco: over $130,000. There was little
solace in the fact that the removal of the filament battery saved
about $500 in power costs. To add insult to injury, the equipment
only carried the service for another six months before being finally
retired and scrapped.

"Audiophools" worrying about "cathode stripping" has nothing whatever
to do with "sleeping sickness." I've yet to see any "audiophool" who
actually knows how a tube works, anyway. You have to expect this
from people who refer to audio phenomina as "air," "stage," "detail,"
"crispness" and other assorted laughable terms.

Thanks for relating the most persuasive example I've ever read of this
obscure phenomenon. I'm sure many of us envy your experience with the
real WE tubes and equipment (I certainly do).

But Gee, dB, I know how a tube works, and I also know the meaning of
"air", "stage", "detail", "crispness" and other assorted terms used by
audio professionals to describe what one hears when critically
listening to a sound system. They are more useful and descriptive
than, "That sounds good", or "That stinks".

If you find these audio terms laughable, how do you deal with the
Latin terms your doctors toss around? Does the term, "squamas cell
carcinoma" cause you to roll on the floor, laughing your ass off? I
mean, that gibberish couldn't possibly mean anything real, right?

sigh

Enjoy your life, dB. Get lots of "air" - air is good. And don't get
"squamas cell carcinoma" - carcinoma is bad, whether you understand
the terminology or not.

Fred

dB

Sidebar: On that particular floor resided many old pieces of gear
from the 1930s, including bays of voice order wire equipment
associated with long gone J and K carrier systems. In them were rows
of bayonet based 101D triodes and 201As, most dating from the 1930s,
some from the '40s. All tested good when pulled after 45+ years of
continuous service. I shudder to think what these old things
would've brought today on fraudBay. The secret to long tube life at
the phone company? Running filaments 10% below rated voltage and
excellent quality elements. The Richardson replacements which came
later were nowhere near the quality of any old WECO tube, and WECO
tubes made in the early '80s were almost as bad.




Good point, a lot of Latin names are purely descriptive in a way that reads
like a child's description, a way that makes "air", "stage", "detail",
"crispness" look erudite and scholastic in comparison. On the other hand,
it all comes down to convention. Any description that seeks to be objective
can only use terms that are agreed in meaning by all who use them. If
"air", "stage", "detail", "crispness" could be mapped to some kind of
spectral variant of an idealised response, then it might be easier to use
them.

wrote:

I'm guessing that the 5xxx industrial tubes were mostly registered in
numerical order.

For the most part.

But does the book give much guidance on who produced
these tubes and when, who relabeled them, and when they stopped being
produced?

Sometimes yes, sometimes no. Somethings are in detail, somethings are
just tiny snippets of info.

I asked on the Tube Collector list, and there is currently a little
debate about who made the design - GE or RCA.

--
Will

On Thu, 18 May 2006 04:34:29 GMT, "Ft.peoplepc.com"
wrote:

Thanks for relating the most persuasive example I've ever read of this
obscure phenomenon. I'm sure many of us envy your experience with the
real WE tubes and equipment (I certainly do). snip

We'd toss them around like toys...tubes were tubes, nothing more. I
felt the same way when I unloaded a box full of NOS 350Bs a few years
back...it's just a well done 6L6. The buyers didn't think so,
enriching me with thousands of dollars. Ditto for the 101A audio
amps.

If you find these audio terms laughable, how do you deal with the Latin
terms your doctors toss around? Does the term, "squamas cell carcinoma"
cause you to roll on the floor, laughing your ass off? I mean, that gibberish
couldn't possibly mean anything real, right? snip

It does to someone like me who's studied Latin and Greek, yes.

Enjoy your life, dB. Get lots of "air" - air is good. And don't get "squamas
cell carcinoma" - carcinoma is bad, whether you understand the terminology
or not. snip

I understand it perfectly.

I do miss those old days, not just for the old, 1930s through '50s
vintage tube toll equipment, either. Everything was designed to
maintained, everyone had a job, and the economy was good....not "good"
like the Bushies and Wall St. lie about today, but REALLY good. Today,
things are in bad shape, whether those living in it want to wake up
and smell the coffee or not. The complex I worked in for years for
both PT&T and AT&T had 1800 people working in it on any given day
shift, with a couple of hundred on swing and graveyard. Now, that
whole complex MAY house about 25 people max at any given time. Where
did all those jobs go? Wally-Fart, Burger King, Starbuck's...the list
is endless.

dB

On Thu, 18 May 2006 09:23:14 -0400, "Warren W. Gay"
wrote:

A lot of guitar amp work is done to create the right kind
of distortion. 3rd order hamonics are ok, as long as the
energy isn't all there (you also want a fairly even distribution
of other harmonics, obviously tapering off at the upper end).
I'll have acquire a few of these babies and try them in the
preamp I built a while ago. snip

If you're out to make noise with a gee-tawr, fine. For high fidelity,
they suck.

DeserTBoB wrote:
On Thu, 18 May 2006 04:34:29 GMT, "Ft.peoplepc.com"
wrote:

Thanks for relating the most persuasive example I've ever read of this
obscure phenomenon. I'm sure many of us envy your experience with the
real WE tubes and equipment (I certainly do). snip

We'd toss them around like toys...tubes were tubes, nothing more. I

It was *nothing* to do radio equipment routines (on non-WECo
designed radios) and replace 2-300 tubes in one day. Of course
*most* of them sold for a dollar or two, not the prices you
mentioned for 310s etc. But by the same token, I used to toss
specially selected 416B gold plated planar triodes (WA6280) by
the bushel too, and those must have cost $200 each. (I worked
on tropo sites, and also tossed, individually, $7000 klystron
tubes too...)

As you noted quite accurately, WECo designed equipment was often
turned down 30-40 years later with some of the original tubes
still working! (Except of course in 43A1 terminal units and X
type SF units! What a pain those were...)

....

I do miss those old days, not just for the old, 1930s through '50s
vintage tube toll equipment, either. Everything was designed to
maintained, everyone had a job, and the economy was good....not "good"
like the Bushies and Wall St. lie about today, but REALLY good. Today,
things are in bad shape, whether those living in it want to wake up
and smell the coffee or not. The complex I worked in for years for
both PT&T and AT&T had 1800 people working in it on any given day
shift, with a couple of hundred on swing and graveyard. Now, that
whole complex MAY house about 25 people max at any given time. Where
did all those jobs go? Wally-Fart, Burger King, Starbuck's...the list
is endless.

I sympathize with your feelings, but can't agree with what you say.

I worked at small places. But the ratio of circuits to people
was about the same. There was a time when each technician on
shift might cover for 200-300 circuits or so. Then it became 2000,
and kept going up.

Today AT&T covers whole regions with a handful of people, and I
have no way to calculate a ratio of circuits to techs that
relates to what we had 40 years ago.

But I *can* tell you what the difference is! Long distance
today costs less than a penny per minute. The actual bill that
we pay for a long distance call still has more to do with the
cost of local telephone service than any other single factor.
And we have the Internet (which is transported on the same long
distance facilities that voice calls are).

To put it mildly, the transformation that modern
telecommunications technology has brought to the world in the
last 40 years has had more to do with *improving* the quality
(and length) of life for the people who have access to it (the
industrialized world) than any other single cause.

Which probably means that without it, you and I would by now be
dead an buried rather than alive, healthy, and kicking on
Usenet!

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

On Thu, 18 May 2006 21:32:37 -0800, (Floyd L.
Davidson) wrote:

It was *nothing* to do radio equipment routines (on non-WECo
designed radios) and replace 2-300 tubes in one day. Of course
*most* of them sold for a dollar or two, not the prices you
mentioned for 310s etc. But by the same token, I used to toss
specially selected 416B gold plated planar triodes (WA6280) by
the bushel too, and those must have cost $200 each. snip

More. The 416C, the last version, went for a nice $460 apiece. The
416s were the backbone of the AT&T Long Lines TD radio network (4 GHz)
for 40 years.

(I worked
on tropo sites, and also tossed, individually, $7000 klystron
tubes too...) snip

We used to send out 3KW klystrons in for rebuilding, if they weren't
too far pitted. That'd save a cool $4K a unit.

As you noted quite accurately, WECo designed equipment was often
turned down 30-40 years later with some of the original tubes
still working! (Except of course in 43A1 terminal units and X
type SF units! What a pain those were...) snip

ACK! SF UNITS! BOOO....HISS!

...

I do miss those old days, not just for the old, 1930s through '50s
vintage tube toll equipment, either. Everything was designed to
maintained, everyone had a job, and the economy was good....not "good"
like the Bushies and Wall St. lie about today, but REALLY good. Today,
things are in bad shape, whether those living in it want to wake up
and smell the coffee or not. The complex I worked in for years for
both PT&T and AT&T had 1800 people working in it on any given day
shift, with a couple of hundred on swing and graveyard. Now, that
whole complex MAY house about 25 people max at any given time. Where
did all those jobs go? Wally-Fart, Burger King, Starbuck's...the list
is endless.

I sympathize with your feelings, but can't agree with what you say.

I worked at small places. But the ratio of circuits to people
was about the same. There was a time when each technician on
shift might cover for 200-300 circuits or so. Then it became 2000,
and kept going up.

Today AT&T covers whole regions with a handful of people, and I
have no way to calculate a ratio of circuits to techs that
relates to what we had 40 years ago.

But I *can* tell you what the difference is! Long distance
today costs less than a penny per minute. The actual bill that
we pay for a long distance call still has more to do with the
cost of local telephone service than any other single factor.
And we have the Internet (which is transported on the same long
distance facilities that voice calls are).

To put it mildly, the transformation that modern
telecommunications technology has brought to the world in the
last 40 years has had more to do with *improving* the quality
(and length) of life for the people who have access to it (the
industrialized world) than any other single cause.

Which probably means that without it, you and I would by now be
dead an buried rather than alive, healthy, and kicking on
Usenet!

On Thu, 18 May 2006 21:32:37 -0800, (Floyd L.
Davidson) wrote:

It was *nothing* to do radio equipment routines (on non-WECo
designed radios) and replace 2-300 tubes in one day. Of course
*most* of them sold for a dollar or two, not the prices you
mentioned for 310s etc. But by the same token, I used to toss
specially selected 416B gold plated planar triodes (WA6280) by
the bushel too, and those must have cost $200 each. snip

More. The 416C, the last version, went for a nice $460 apiece. The
416s were the backbone of the AT&T Long Lines TD radio network (4 GHz)
for 40 years.

(I worked
on tropo sites, and also tossed, individually, $7000 klystron
tubes too...) snip

We used to send out 3KW klystrons in for rebuilding, if they weren't
too far pitted. That'd save a cool $4K a unit.

As you noted quite accurately, WECo designed equipment was often
turned down 30-40 years later with some of the original tubes
still working! (Except of course in 43A1 terminal units and X
type SF units! What a pain those were...) snip

ACK! SF UNITS! BOOO....HISS!

...

I do miss those old days, not just for the old, 1930s through '50s
vintage tube toll equipment, either. Everything was designed to
maintained, everyone had a job, and the economy was good....not "good"
like the Bushies and Wall St. lie about today, but REALLY good. Today,
things are in bad shape, whether those living in it want to wake up
and smell the coffee or not. The complex I worked in for years for
both PT&T and AT&T had 1800 people working in it on any given day
shift, with a couple of hundred on swing and graveyard. Now, that
whole complex MAY house about 25 people max at any given time. Where
did all those jobs go? Wally-Fart, Burger King, Starbuck's...the list
is endless.

I sympathize with your feelings, but can't agree with what you say.

I worked at small places. But the ratio of circuits to people
was about the same. There was a time when each technician on
shift might cover for 200-300 circuits or so. Then it became 2000,
and kept going up.

Today AT&T covers whole regions with a handful of people, and I
have no way to calculate a ratio of circuits to techs that
relates to what we had 40 years ago.

But I *can* tell you what the difference is! Long distance
today costs less than a penny per minute. The actual bill that
we pay for a long distance call still has more to do with the
cost of local telephone service than any other single factor.
And we have the Internet (which is transported on the same long
distance facilities that voice calls are). snip

You pay a penny a minute (cell phoners generally pay zero per minute)
and local POTS goes up and up to compensate. Now that the Bell System
is about 75% back together, things will change.

To put it mildly, the transformation that modern
telecommunications technology has brought to the world in the
last 40 years has had more to do with *improving* the quality
(and length) of life for the people who have access to it (the
industrialized world) than any other single cause. snip

How it relates to "length of life," I have not a clue.

Which probably means that without it, you and I would by now be
dead an buried rather than alive, healthy, and kicking on
Usenet! snip

Somehow, I'd lay that increase at better medical care I get from my
non-profit HMO than communications availability. As for POTS and LD
service, it's no better than it was circa 1990, and probably a little
worse. Reorders in peak periods are common now; they were a mortal
sin back in the '70s. Transmission impairments due to over squeezing
bitstuffing schemes yields degraded transmission qauality as well on
DDD access, but with so many people on those rotten cell phones, it's
hard to pin down where the problem lies.

dB

DeserTBoB wrote:
On Thu, 18 May 2006 21:32:37 -0800, (Floyd L.
Davidson) wrote:
To put it mildly, the transformation that modern
telecommunications technology has brought to the world in the
last 40 years has had more to do with *improving* the quality
(and length) of life for the people who have access to it (the
industrialized world) than any other single cause. snip

How it relates to "length of life," I have not a clue.

The entire health care delivery system is *totally* dependent
upon it.

We *don't* want to go back to 1950...

Which probably means that without it, you and I would by now be
dead an buried rather than alive, healthy, and kicking on
Usenet! snip

Somehow, I'd lay that increase at better medical care I get from my
non-profit HMO than communications availability.

How do you think they are able to provide better care!

As for POTS and LD
service, it's no better than it was circa 1990,

I don't agree. SS7 is one difference, and of course in 1990
digital switching was ubiquitous for LD, but most of the US
was about 33% digital.

On the other hand, I'd agree that since about 1995 we haven't
gone far. But the decade from 1985 to 1995 was the one where
the *huge* change took place.

and probably a little
worse. Reorders in peak periods are common now; they were a mortal
sin back in the '70s. Transmission impairments due to over squeezing
bitstuffing schemes yields degraded transmission qauality as well on
DDD access, but with so many people on those rotten cell phones, it's
hard to pin down where the problem lies.

I don't think it is so much that people are on cell phones, as
it is that there is no longer *anyone paying attention* to what
any given switch is actually *doing*.

The network is monitored from a centralized NOC, where nobody
knows what any particular switch is actually doing. The don't
see specifics, only trends. If there is a trend for some
particular problem, then someone will analyze it to death, and
maybe even find a cause. But if some particular switch as a
single problem, it just may *never* get notice if it doesn't
actually cause an alarm.

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

On Thu, 18 May 2006 22:35:45 -0800, (Floyd L.
Davidson) wrote:

I don't agree. SS7 is one difference, and of course in 1990
digital switching was ubiquitous for LD, but most of the US
was about 33% digital. snip

SS7 was already in deployment in major toll centers by '90. I was
involved in that regarding international trunking of Pacific Rim
countries from an INTELSAT Class A earth station to various 4ESS
switches in California.

On the other hand, I'd agree that since about 1995 we haven't
gone far. But the decade from 1985 to 1995 was the one where
the *huge* change took place. snip

Not really. The POTS user wasn't really affected for the better by
SS7 deployment. The big change for them was the move of toll
switching from 4A crossbar to 4ESS machines and the move of trunks off
of FM radio and coaxial cable onto lightwave. That difference was
huge in the '80s.

and probably a little
worse. Reorders in peak periods are common now; they were a mortal
sin back in the '70s. Transmission impairments due to over squeezing
bitstuffing schemes yields degraded transmission qauality as well on
DDD access, but with so many people on those rotten cell phones, it's
hard to pin down where the problem lies.

I don't think it is so much that people are on cell phones, as
it is that there is no longer *anyone paying attention* to what
any given switch is actually *doing*. snip

Quality doesn't matter to dumb consumers. If it did, there would be
very few cellular customers who were happy with their service. Now,
hosed up transmission, dropped called, and all the usual cell phone
garbage is somehow "normal." If it were happening in the regulated
era, PUCs and the FCC would have been overflowing with complaints.

The network is monitored from a centralized NOC, where nobody
knows what any particular switch is actually doing. The don't
see specifics, only trends. If there is a trend for some
particular problem, then someone will analyze it to death, and
maybe even find a cause. But if some particular switch as a
single problem, it just may *never* get notice if it doesn't
actually cause an alarm. snip

You're talking to someone who's actually been in the AT&T NOC in
Bedminster. They know a LOT about what each switch is doing, trust me
on this. Of course, the competitors, MCI (now VZ) and those other
losers haven't got a clue until there's a major failure. The Loma
Prieta earthquake in 1987 made it abundently clear that MCI was
somewhat of a fraud. Not only did all their switches fail, but their
"NOC" had no clue as to how to reroute traffic. Even after the
Oakland toll center was condemned, the 4ESS kept right on putting
traffic through, although in simplex mode.

dB

DeserTBoB wrote:
On Thu, 18 May 2006 22:35:45 -0800, (Floyd L.
Davidson) wrote:

I don't agree. SS7 is one difference, and of course in 1990
digital switching was ubiquitous for LD, but most of the US
was about 33% digital. snip

SS7 was already in deployment in major toll centers by '90. I was

Sure, but "in major toll centers" is *very* limiting, because
the advantages of SS7 were only realized when it was extended to
the Local Exchange Carriers. Given that the first full
implementation (by Sprint) for a toll network was in 1988 (and
AT&T very shortly after that), there had been no incentive for
LECs to implement SS7 *until* 1990. In fact, many of them were
still using non-digital switching systems that could not make
use of SS7.

The real import of SS7 was not available until *after* 1990,
and it was rather rapidly adopted between then and 1995.

involved in that regarding international trunking of Pacific Rim
countries from an INTELSAT Class A earth station to various 4ESS
switches in California.

Exactly. And it wasn't until *that* was complete before the
LECs could actually make use of it.

On the other hand, I'd agree that since about 1995 we haven't
gone far. But the decade from 1985 to 1995 was the one where
the *huge* change took place. snip

Not really. The POTS user wasn't really affected for the better by
SS7 deployment.

Not by the SS7 deployment of the IXC's! But they were certainly
affected between 1990 and 1995 by the massive move of LECs to SS7.

The big change for them was the move of toll
switching from 4A crossbar to 4ESS machines and the move of trunks off
of FM radio and coaxial cable onto lightwave. That difference was
huge in the '80s.

Yes... the *late* '80s. But note again that you are considering
only Long Distance (4ESS etc.), not line switching by LECs.

and probably a little
worse. Reorders in peak periods are common now; they were a mortal
sin back in the '70s. Transmission impairments due to over squeezing
bitstuffing schemes yields degraded transmission qauality as well on
DDD access, but with so many people on those rotten cell phones, it's
hard to pin down where the problem lies.

I don't think it is so much that people are on cell phones, as
it is that there is no longer *anyone paying attention* to what
any given switch is actually *doing*. snip

Quality doesn't matter to dumb consumers. If it did, there would be
very few cellular customers who were happy with their service. Now,
hosed up transmission, dropped called, and all the usual cell phone
garbage is somehow "normal." If it were happening in the regulated
era, PUCs and the FCC would have been overflowing with complaints.

True for the quality of transmission characteristics. But of
course there are other measures of "quality", and some of them
*do* matter to "dumb consumers". Price of course is a major
factor. Availability is another. What you have listed are
measures of only the transmission quality. But we knew very
well even in the 1930's (when the Telecommunications Act
essentially allowed a set of standards which were a target was
recommended, not required) that customers who with horrible
service over barbed wire fence... were very happy to just *have*
a telephone. This isn't something new, caused by cell phones...

The network is monitored from a centralized NOC, where nobody
knows what any particular switch is actually doing. The don't
see specifics, only trends. If there is a trend for some
particular problem, then someone will analyze it to death, and
maybe even find a cause. But if some particular switch as a
single problem, it just may *never* get notice if it doesn't
actually cause an alarm. snip

You're talking to someone who's actually been in the AT&T NOC in
Bedminster.

I've spent a great deal of time studying how and why a NOC
functions the way it does (or doesn't), in efforts to design
better trouble ticketing systems.

They know a LOT about what each switch is doing, trust me
on this.

Trust me, there is a *huge* amount of what is going on that
we don't know. Remember back when every switch was maintained
by a crew that had at least a few old switchmen... and they
used to be so tuned to what the switch *sounded* like, that
when they heard an unusual noise they set about to figure out
what was wrong? We don't have that level of familiarity with
the switching systems anymore.

I wrote software to analyze log reports at the Fairbanks Toll
Center back in the early 1990's. This is a topic that I have
more than a casual introduction to. The biggest problem is
spotting unique troubles that are *not* trends. For example,
a digit receiver that drops the number every 5th time it is
used... will most likely *never* be discovered. From a signal
device, the numbers are not high enough to trigger anyone's
attention. If the device itself does not go into alarm, it
will continue to dump call forever.

Of course, the competitors, MCI (now VZ) and those other
losers haven't got a clue until there's a major failure.

Ha ha, you think AT&T is any better????

AT&T is so hung up on how to administer the operations of a
large company that they can't *operate* any given small part of
it effectively. The result is an "efficient" top level,
managing a large number of ineffective (hence not profitable)
operations.

Basically they can't implement anything in any part of the
company unless it is something that can be done company wide in
an efficient manner.

The Loma
Prieta earthquake in 1987 made it abundently clear that MCI was
somewhat of a fraud. Not only did all their switches fail, but their
"NOC" had no clue as to how to reroute traffic. Even after the
Oakland toll center was condemned, the 4ESS kept right on putting
traffic through, although in simplex mode.

We can find just as many isolated incidents of AT&T being just
as confused. Ask someone why they have both a 4ESS *and* a
DMS-200 in the Anchorage Toll Center...

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

On Fri, 19 May 2006 09:15:37 -0800, (Floyd L.
Davidson) wrote:

Yes... the *late* '80s. But note again that you are considering
only Long Distance (4ESS etc.), not line switching by LECs. snip

Well, considering that GTE was still running SXS in the majority of
their offices in California, that would be true...for them. By the
'80s, the RBOCs were already phasing out 1A-ESS to be replaced by
5ESS, which was already SS7-capable as installed. GT was saddled with
other problems too, like Kellogg X carrier on local cable pairs due
to underinvestment in copper by both them and their predecessors. To
upgrade or risk losing service territory, GT went to the failed
Automatic Electric GTD5, which was obsolete when they installed them.
They were, however, a massive improvement over GT's horridly
maintained SXS with directors.

I've spent a great deal of time studying how and why a NOC
functions the way it does (or doesn't), in efforts to design
better trouble ticketing systems.

They know a LOT about what each switch is doing, trust me
on this.

Trust me, there is a *huge* amount of what is going on that
we don't know. Remember back when every switch was maintained
by a crew that had at least a few old switchmen... and they
used to be so tuned to what the switch *sounded* like, that
when they heard an unusual noise they set about to figure out
what was wrong? We don't have that level of familiarity with
the switching systems anymore. snip

That was true in the SXS and XBAR days, but died with ESS. Most 4A
men could tell when the switch was going to dump a card due to a bad
link frame or other problem just by the sound of the relay sequence
while putting a 101 call through the switch.

I wrote software to analyze log reports at the Fairbanks Toll
Center back in the early 1990's. This is a topic that I have
more than a casual introduction to. The biggest problem is
spotting unique troubles that are *not* trends. For example,
a digit receiver that drops the number every 5th time it is
used... will most likely *never* be discovered. From a signal
device, the numbers are not high enough to trigger anyone's
attention. If the device itself does not go into alarm, it
will continue to dump call forever. snip

Plus, you were probably stuck with ALASCOM, too!

Ha ha, you think AT&T is any better???? snip

Not anymore, but in the analog days after the Wendover disaster in
'61, AT&T Long LInes was VERY good at isolating and rerouting around
trouble. When Bob Allen took over as CEO of AT&T, all that went to
crap.

Basically they can't implement anything in any part of the
company unless it is something that can be done company wide in
an efficient manner. snip

Nice try, but simply not true. The failuire of AT&T in later years
was due to one reason and one reason only: incompetence at the top.

We can find just as many isolated incidents of AT&T being just
as confused. Ask someone why they have both a 4ESS *and* a
DMS-200 in the Anchorage Toll Center... snip

NorTel = NO tel

DeserTBoB wrote:
On Fri, 19 May 2006 09:15:37 -0800, (Floyd L.
Davidson) wrote:

Yes... the *late* '80s. But note again that you are considering
only Long Distance (4ESS etc.), not line switching by LECs. snip

Well, considering that GTE was still running SXS in the majority of
their offices in California, that would be true...for them. By the
'80s, the RBOCs were already phasing out 1A-ESS to be replaced by

"Phasing out" is not the same as "phased out". It wasn't anywhere
near completed by 1990.

5ESS, which was already SS7-capable as installed. GT was saddled with
other problems too, like Kellogg X carrier on local cable pairs due
to underinvestment in copper by both them and their predecessors. To
upgrade or risk losing service territory, GT went to the failed
Automatic Electric GTD5, which was obsolete when they installed them.
They were, however, a massive improvement over GT's horridly
maintained SXS with directors.

Granted that all of that is true, but it doesn't make the RBOC's
all that much better... :-)

I wrote software to analyze log reports at the Fairbanks Toll
Center back in the early 1990's. This is a topic that I have
more than a casual introduction to. The biggest problem is
spotting unique troubles that are *not* trends. For example,
a digit receiver that drops the number every 5th time it is
used... will most likely *never* be discovered. From a signal
device, the numbers are not high enough to trigger anyone's
attention. If the device itself does not go into alarm, it
will continue to dump call forever. snip

Plus, you were probably stuck with ALASCOM, too!

Which at the time was significantly *better* than AT&T. Of
course since 1995 it *is* AT&T.

(I should probably qualify that statement. When Pacific Telecom
Inc owned Alascom they had *exactly* the same upper management
problems that AT&T did: a total lack of vision to encompass the
future of telecommunications using modern technology. The
biggest difference was size, which translates to resourses. The
PTI Board of Directors and the Alascom Board of Directors,
assisted by their management team, came to the conclusion in the
late 1980's that they had no idea what direction the company
should go, and decided to sell it to AT&T. It took them until
1995 to manage to pull that off. But while AT&T's Board of
Directors did seem to know where they wanted to go, they were
totally unable to transform their management team into one that
could move in that direction. See the below discussion about
Allen, Armstrong, et al for more opinion on that fiasco.)

Ha ha, you think AT&T is any better???? snip

Not anymore, but in the analog days after the Wendover disaster in
'61, AT&T Long LInes was VERY good at isolating and rerouting around
trouble. When Bob Allen took over as CEO of AT&T, all that went to
crap.

Which of course demonstrates *exactly* my point.

Except that I wouldn't say Bob Allen was at fault in quite the
manner you describe. His failing was not being able to root out
the entrenched Long Lines hold on the upper levels of AT&T
management. He was replaced because he failed at that. His
replacement was also replaced for the same reason, as was the
next replacement...

And of course the reason AT&T failed, and has been sold, is
because nobody was actually ever successful at restructuring the
upper management to operate in a way that made sense with modern
technology.

Basically they can't implement anything in any part of the
company unless it is something that can be done company wide in
an efficient manner. snip

Nice try, but simply not true. The failuire of AT&T in later years
was due to one reason and one reason only: incompetence at the top.

That is exactly what I said.

Innovation at the lower levels was absolutely ignored by upper
level management when making decisions. They would not allow a
regional or departmental (or any other from of compartmentalism)
managment team to implement anything unique to themselves. If
it could not be micromanaged from the upper levels, it was not
allowed. It had to be "one size fits all". That is perhaps
efficient somewhere, but not for the dominant long distance
carrier in the US.

We can find just as many isolated incidents of AT&T being just
as confused. Ask someone why they have both a 4ESS *and* a
DMS-200 in the Anchorage Toll Center... snip

NorTel = NO tel

Yeah, sure. And that is the sort of brainlessness that cause
AT&T to fail.

That is, for example, why Northern Telecom in a ten year period
from 1975 to 1985 managed to grab 40% of the US market? (Not
the least of reasons being they were first with an all digital
switch that included a digital network fabric.)

But more to the point, the reason there is a DMS-200 in the
Anchorage Toll Center is because the 4ESS cannot do what the
DMS-200 does. Therefore the DMS-200 stays. The 4ESS was
installed simply because when AT&T bought the business in Alaska
they could not imagine a Toll Center without a 4ESS. Without
determining whether it was required or even useful, they
installed one. It was neither.

On the other hand, I've never heard of anything a 4E can do that
a DMS-200 won't also do. I don't really see either of them as
significantly better than the other. The same is true of the 5E
compared to a DMS-100. The one catch might be that a
DMS-100/200 is more flexible than a 5E.

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

In article , says...
On Thu, 18 May 2006 21:32:37 -0800, (Floyd L.
Davidson) wrote:

It was *nothing* to do radio equipment routines (on non-WECo
designed radios) and replace 2-300 tubes in one day. Of course
*most* of them sold for a dollar or two, not the prices you
mentioned for 310s etc. But by the same token, I used to toss
specially selected 416B gold plated planar triodes (WA6280) by
the bushel too, and those must have cost $200 each. snip

More. The 416C, the last version, went for a nice $460 apiece. The
416s were the backbone of the AT&T Long Lines TD radio network (4 GHz)
for 40 years.

(I worked
on tropo sites, and also tossed, individually, $7000 klystron
tubes too...) snip

We used to send out 3KW klystrons in for rebuilding, if they weren't
too far pitted. That'd save a cool $4K a unit.

As you noted quite accurately, WECo designed equipment was often
turned down 30-40 years later with some of the original tubes
still working! (Except of course in 43A1 terminal units and X
type SF units! What a pain those were...) snip

ACK! SF UNITS! BOOO....HISS!

You sound like an Air Force Tech Controller. How about those lenkherts
(sp?) eh? 2600hz and all for you! Wink!

-Bart

bart wrote:
In article , says...
As you noted quite accurately, WECo designed equipment was often
turned down 30-40 years later with some of the original tubes
still working! (Except of course in 43A1 terminal units and X
type SF units! What a pain those were...) snip

ACK! SF UNITS! BOOO....HISS!

You sound like an Air Force Tech Controller. How about those lenkherts
(sp?) eh? 2600hz and all for you! Wink!

If you've never spent all day, weeks on end, adjusting 255A
relays or X-Type SF Units...

Keep in mind that the Bell System was designed by geniuses to be
operated by idiots.

(On the other hand, in Alaska we had a PSTN that was designed by
idiots, and because of that required geniuses to operate it.)

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

In article , (Floyd L.
Davidson) wrote:

DeserTBoB wrote:
On Thu, 18 May 2006 22:35:45 -0800, (Floyd L.
Davidson) wrote:

I don't agree. SS7 is one difference, and of course in 1990
digital switching was ubiquitous for LD, but most of the US
was about 33% digital. snip

SS7 was already in deployment in major toll centers by '90. I was

Sure, but "in major toll centers" is *very* limiting, because
the advantages of SS7 were only realized when it was extended to
the Local Exchange Carriers. Given that the first full
implementation (by Sprint) for a toll network was in 1988 (and
AT&T very shortly after that), there had been no incentive for
LECs to implement SS7 *until* 1990. In fact, many of them were
still using non-digital switching systems that could not make
use of SS7.

I thought the first installation of SS7 in the Bell system was connected
to the last of the crossbar toll switches that Bell installed, at least
that is what Bell claimed in an old issue of the "Bell Labs Record" IIRC?


Regards,

John Byrns


Surf my web pages at, http://users.rcn.com/jbyrns/

On Fri, 19 May 2006 13:08:22 -0800, (Floyd L.
Davidson) wrote:

Granted that all of that is true, but it doesn't make the RBOC's
all that much better... :-) snip

The TELSAM scores told the tale...the "indies" sucked. Some of the
worst came from various GTE properties, with United a close second.
Even some of the few "mom 'n pop" telcos out there scored better.

Which at the time was significantly *better* than AT&T. Of
course since 1995 it *is* AT&T. snip

(I should probably qualify that statement. When Pacific Telecom
Inc owned Alascom they had *exactly* the same upper management
problems that AT&T did: a total lack of vision to encompass the
future of telecommunications using modern technology. The
biggest difference was size, which translates to resourses. The
PTI Board of Directors and the Alascom Board of Directors,
assisted by their management team, came to the conclusion in the
late 1980's that they had no idea what direction the company
should go, and decided to sell it to AT&T. It took them until
1995 to manage to pull that off. But while AT&T's Board of
Directors did seem to know where they wanted to go, they were
totally unable to transform their management team into one that
could move in that direction. See the below discussion about
Allen, Armstrong, et al for more opinion on that fiasco.) snip

When I went to the Satellite Transmission Systems/Varian factory in
Melbourne, FL to check on an order of IBS modems, there, in the back,
was an old, beat to crap Alascom "mobile unit" that they'd somehow
shoehorned into an old GMC motorhome...you know, the fiberglas ones
from the '70s? It was actually worse than some of the engineering
boondoggles I'd seen out of New Jersey...but not by much!

Except that I wouldn't say Bob Allen was at fault in quite the
manner you describe. His failing was not being able to root out
the entrenched Long Lines hold on the upper levels of AT&T
management. He was replaced because he failed at that. His
replacement was also replaced for the same reason, as was the
next replacement... snip

All wrong. Bob Allen was "replaced" because Leslie Stahl on CBS outed
him on "60 Minutes" for being indifferent about the company's (and the
employees') situation at the time. Prior to the "60 Minutes"
surprise, Wall St. loved Allen, because every time T's common stock
would take a dip, he'd lay off more people, and thus buoy the stock.
When Allen got thrown out, there weren't enough "indians" to do the
work in the field, while management was as fat as ever. Armstrong did
one good thing, in that the next round of downsizing was mostly lower
and middle management, who'd been building empires and licking Allen
and his underlings' boots for years. When Allen left, there were 1.15
managers for every working employee. Chew on that for a moment.

And of course the reason AT&T failed, and has been sold, is
because nobody was actually ever successful at restructuring the
upper management to operate in a way that made sense with modern
technology. snip

Technology wasn't the problem...it was failed upper management,
period. AT&T had all the resources, and, instead of capitalizing on
that, they put the guy in there as CEO that 1.) approved the AT&T PC
6300 and 7300 disaster, 2.) wrecked Western Electric in the '70s, 3.)
headed up the horrific American Bell disaster, 4.) decided to try to
cover his PC and biz technology goofs by buying another loser, NCR,
for $13.8 BILLION (later selling it quietly for dimes on the dollar),
and 5.) decided too late in the game that by pleasing Wall St
analysts, he could save the company by keeping its common stock price
artificially high.

Innovation at the lower levels was absolutely ignored by upper
level management when making decisions. They would not allow a
regional or departmental (or any other from of compartmentalism)
managment team to implement anything unique to themselves. If
it could not be micromanaged from the upper levels, it was not
allowed. It had to be "one size fits all". That is perhaps
efficient somewhere, but not for the dominant long distance
carrier in the US. snip

Not true. During Allen's "reign of stupidity," district and above
level managers kept complaining about having to make decisions they
felt were "too small" to be their concern, and so, decision making was
driven to the absolute lowest tier, sometimes to the techs themselves,
with no clue as to strategy, funding, logistics...nothing. What
emerged was even more "empire building" as first levels and even
techs, left to their won devices, would try to carve out a
layoff-proof niche in the crumbling AT&T structure.

NorTel = NO tel

Yeah, sure. And that is the sort of brainlessness that cause
AT&T to fail.

That is, for example, why Northern Telecom in a ten year period
from 1975 to 1985 managed to grab 40% of the US market? snip

Ask Pac Bell (later SBC) about NorTel switches. PB bought a ****load
of them right after Divestiture and wound up wrecking them out in as
little as three or four years due to reliability and support problems,
opting to go with the 5E almost exclusively.

(Not the least of reasons being they were first with an all digital
switch that included a digital network fabric.)

But more to the point, the reason there is a DMS-200 in the
Anchorage Toll Center is because the 4ESS cannot do what the
DMS-200 does. Therefore the DMS-200 stays. The 4ESS was
installed simply because when AT&T bought the business in Alaska
they could not imagine a Toll Center without a 4ESS. Without
determining whether it was required or even useful, they
installed one. It was neither. snip

The DMS-200 could do end office functions. The 4E was a huge toll
switch, period. Next? The 5E could do both (well, not being a HUGE
toll switch, but a medium toll switch), and more, although it, too,
had design problems which took some years to fix.

On the other hand, I've never heard of anything a 4E can do that
a DMS-200 won't also do. snip

I have...it'll last 50-100 years. DMS-200s were good for...five? Ten
at the outside?

I don't really see either of them as
significantly better than the other. The same is true of the 5E
compared to a DMS-100. The one catch might be that a
DMS-100/200 is more flexible than a 5E. snip

Why were 5Es outselling DMS-100s almost 5 to 1 after it became common
knowledge that NorTel couldn't support their own product? If it
weren't for the 5E, Lucent would be gone already. It was their only
profitable and in-demand big product line for a long, long time. No
one buys 4Es anymore, either...the ones in service just get added on
to and keep on going.

On Fri, 19 May 2006 19:42:25 -0400, bart wrote:

In article , says...

You sound like an Air Force Tech Controller. snip

I was USAF, but not for telcom.

How about those lenkherts
(sp?) eh? 2600hz and all for you! Wink! snip

Lenkurt actually built some good, although quirky, stuff back in the
day before GTE gutted them. Lenkert 75A and 775A MW radios were as
reliable as WECO counterparts, although their protection switching
arrangement was a little hosed up. Most of the quality of those radio
was, basically, due to the Varian TWTs, I'm sure. Lenkurt could also
give you 12 channels of P-T-P MW for about half of what WECO could,
and without all that unneeded WLEL gear that HAD to be sold with each
WECO radio installation. I worked on almost all WECO radios from the
TA (2 GHz) to the AR6A (6 GHz, single side band AM...an unmitigated
disaster), and I wouldn't sell Lenkurt stuff completely short. Some
of their stuff, though, was just plain...weird.

Worst MW radio I ever saw: Collins.

Most interesting piece of Lenkurt gear I worked with: 51A remote
telemetry system...same system that, as of 1990, was controlling
everything inside Grand Coulee Dam for the DoI.

Once word came down that GTE was axing Lenkurt and Automatic Electric
and the layoffs started, you couldn't get too much good out of Lenkurt
up there in Sunnyvale. Another American company bit the dust.

Two other small indies that built good stuff back in "the
day"...Farinon and Lynch.

dB

In article ,
(John Byrns) wrote:

In article , (Floyd L.
Davidson) wrote:

DeserTBoB wrote:
On Thu, 18 May 2006 22:35:45 -0800, (Floyd L.
Davidson) wrote:

I don't agree. SS7 is one difference, and of course in 1990
digital switching was ubiquitous for LD, but most of the US
was about 33% digital. snip

SS7 was already in deployment in major toll centers by '90. I was

Sure, but "in major toll centers" is *very* limiting, because
the advantages of SS7 were only realized when it was extended to
the Local Exchange Carriers. Given that the first full
implementation (by Sprint) for a toll network was in 1988 (and
AT&T very shortly after that), there had been no incentive for
LECs to implement SS7 *until* 1990. In fact, many of them were
still using non-digital switching systems that could not make
use of SS7.

I thought the first installation of SS7 in the Bell system was connected
to the last of the crossbar toll switches that Bell installed, at least
that is what Bell claimed in an old issue of the "Bell Labs Record" IIRC?

Oops, sorry, please cancel that, I was thinking of the first Bell system
installation of SS6 which connected the last crossbar Toll Switch
installed in the Bell System with the first ESS Toll Switch installed in
the Bell System.


Regards,

John Byrns


Surf my web pages at, http://users.rcn.com/jbyrns/

On Fri, 19 May 2006 16:34:31 -0800, (Floyd L.
Davidson) wrote:

(On the other hand, in Alaska we had a PSTN that was designed by
idiots, and because of that required geniuses to operate it.) snip

GTE was built by idiots, putting together broken down mom 'n pop
locals, and was run by idiots. I know...my father-in-law was there
and saw it all. It's good that Bell Atlantic was the surviving
company of the VZ merger; else, the whole works would've been eaten up
by Whitacre at SBC...and still may be.

Never sell Whitacre short. He's a Bell System old timer in the best
tradition, and knows what he's doing. Eating AT&T for him was most
likely a "See? Told ya so" to the Noo Joisey morons that ruined T and
kept the associated companies under their thumbs for decades .
Whitacre dreams of reuniting the Bell System, but doesn't seem to face
the fact that when and if that happens, reregulation will naturally
come with it....his only flaw of strategic vision I've seen so far.