[GerryE123]

Hi:

There's a seller on eBay selling PCC88s for typical 6.3v applications and
making the claim "the 7 volt heater means it will last longer". I'm
wondering if this is false and if in fact the opposite may be true? Thanks!

Gerry
P.S. If you have been around RAT for awhile, It shouldn't be too hard to
guess who the seller is.

[West]

"GerryE123" wrote in message
...
Hi:

There's a seller on eBay selling PCC88s for typical 6.3v applications and
making the claim "the 7 volt heater means it will last longer". I'm
wondering if this is false and if in fact the opposite may be true?
Thanks!

Gerry
P.S. If you have been around RAT for awhile, It shouldn't be too hard to
guess who the seller is.

Hi Gerry, What will happen to an ordinary light bulb if you increase the
voltage? It may be brighter but will it last as long?

[Chris Hornbeck]

On Thu, 20 Sep 2007 21:43:28 -0700, Bret Ludwig
wrote:

" higher heater specification"

Gotta love the spin.



" of 7 volts producing a much
longer life and lower noise threshold when used in place of
ECC88/6DJ8."

Bull****. Of course.

Maybe the same thing bugs me as bugs you:

What's so terrible about saying that the advertised valves
are real Telefunkens but need a different heater voltage
to operate properly? Is the truth so horrible that it can't
be told?

What kind of world is this, anyway? (Rhetorical question;
I probably don't want to know.)


Thanks, as always,

Chris Hornbeck

[John Byrns]

In article .com,
Bret Ludwig wrote:

If you increase the voltage across a light bulb two things happen: it
gives off a lot more light and the light is much more white or bluish.
The old tungsten photo lights were just regular bulbs with a design
center around 70-80 volts so the 110 volt standard AC would make their
color spectrum much more white. You could use regular house bulbs if
you gave them 140-160 volts. Their life would plummet of course.

Photographers bought expensive droppers so they could run them at
half voltage for posing then kick them up for the shoot. They never
figured out that by rewiring the autoformer as a booster instead of a
bucker regular house bulbs would work at 1/10 the cost.

Maybe one did try it but found smoke issuing from the autotransformer
when he applied 120 volts to the 70-80 volt tap!


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[robert casey]

GerryE123 wrote:
Hi:

There's a seller on eBay selling PCC88s for typical 6.3v applications and
making the claim "the 7 volt heater means it will last longer". I'm
wondering if this is false and if in fact the opposite may be true? Thanks!


Don't know about the life claim, but preamp tubes run on reduced heater
voltage can be more linear. Tubes like 12AX7 where the plate currents
are fractions of mA's. 12V tubes run at 10.5V or so. &V run at 6.3V
would yield similar results if these tubes are like 12AX7s used in
preamps and other low current circuits.

[robert casey]

Photographers bought expensive droppers so they could run them at
half voltage for posing then kick them up for the shoot. They never
figured out that by rewiring the autoformer as a booster instead of a
bucker regular house bulbs would work at 1/10 the cost.


You could just use a rectifier diode in series with the photographer
bulbs to run them at the power level they'd see run of an 80V supply.
Then short across the diode when taking the picture. Should be a fairly
cheap box to build.

[Johnny Tang]

PCC88 was designed to use 7volt for the filament supply. I am using the TFK
PCC88 in my clone Audio Research SP10. They are working really good and I
just love them.

It can be used with 6.3V but the characteristic change a bit. However, the
good thing is that it will last much longer....




"GerryE123" ...
Hi:

There's a seller on eBay selling PCC88s for typical 6.3v applications and
making the claim "the 7 volt heater means it will last longer". I'm
wondering if this is false and if in fact the opposite may be true?
Thanks!

Gerry
P.S. If you have been around RAT for awhile, It shouldn't be too hard to
guess who the seller is.

[GerryE123]

"West" wrote:

Hi Gerry, What will happen to an ordinary light bulb if you increase the
voltage? It may be brighter but will it last as long?

Hi West:

Isn't the question I asked the opposite of what you wrote? My question was
what happens when a 7v tube is run on 6.3v.

Gerry

[GerryE123]

"Johnny Tang" wrote:

It can be used with 6.3V but the characteristic change a bit. However, the
good thing is that it will last much longer....

What evidence do you have, theoretical or empirical, to support this claim?
Did you buy them from the seller on eBay? If yes, are you saying this based
on the seller's eBay description?

Gerry

[tubegarden]

On Sep 22, 9:03?am, "GerryE123" wrote:

What evidence do you have, theoretical or empirical, to support this claim?


Hi RATs!

I am using 8SN7-GTB in my Ella. It was designed for 6SN7.

Sounds very good

I don't worry about lifetime. They are $4.30 NOS, 6SN7 are $21.95 (and
up) NOS. Even new Chinese 6SN7 are $9.95.

I would rather spend my money on caps and NOS 6528

Happy Ears!
Al

[tubegarden]

On Sep 22, 2:20?pm, Bret Ludwig wrote:

Worry about performance-the tube will not perform properly with that
low a heater supply. If you insist on using them at least have the ass
to build an 8V supply.

Incidentally, I've heard it and it doesn't sound all that good. But
to you, good is probably bad-you like a good cow slobber sundae now
and again, I take it. Sonically speaking.


Hi RATs!

Thank you, Bret.

It is always nice to be insulted by someone like you

Keeps up my morale 8^D

Happy Ears!
Al