Hi group, do any of you old timers, like me ), ever remember seeing an
electronic megaphone from the 50's that was brown hammertone, named LOUD
HAILER on the side, used vacuum tubes and A & B batteries? I swear, my
scoutmaster had one when I was in Troop 4 waaaay back in 1962 or so. It had
three tubes, a pair of push pull outputs and a preamp. I think they were the
3 volt filament tubes like the ones in the big ol' portables of that era. It
was not a powerhouse, but as a kid I thought it was the neatest thing. When
you squeezed the trigger, it took about a second for the tubes to warm up
before you could use it. As I recall, used two 671/2 volt batteries and a
couple of D cells to light the tubes. I would really like to find one of
these, the solid state Fanons would blow this guy out of the water, but this
thing was classy.
Regards,
Tom

patrick wrote:

"John Stewart" schreef in bericht
...


"t.hoehler" wrote:

Hi group, do any of you old timers, like me ), ever remember seei=
ng an
electronic megaphone from the 50's that was brown hammertone, named=
LOUD
HAILER on the side, used vacuum tubes and A & B batteries? I swear=
, my
scoutmaster had one when I was in Troop 4 waaaay back in 1962 or so=
=2E It
had
three tubes, a pair of push pull outputs and a preamp. I think they=
were
the
3 volt filament tubes like the ones in the big ol' portables of tha=
t
era. It
was not a powerhouse, but as a kid I thought it was the neatest thi=
ng.
When
you squeezed the trigger, it took about a second for the tubes to w=
arm
up
before you could use it. As I recall, used two 671/2 volt batteries=
and
a
couple of D cells to light the tubes. I would really like to find o=
ne of
these, the solid state Fanons would blow this guy out of the water,=
but
this
thing was classy.
Regards,
Tom

Probably a 1J6G dual Triode running Class B driven by a 1H4G.
Mic would be a carbon job something like what is in a Bell handset.
If everything worked you could probably get a dependable 1.5 Watts
after output transformer losses.

Cheers, John Stewart

Tom,

I think I have the microphone cell for a loudhailer.
It is an unusual looking element, a 55mm (2 1/4") diameter by 12mm (1/2=
")
thick brown backelite disk having 2 terminals on the back. The front is=

devided in 2 sections and filled with a black material and sealed with
transparant plastic foil. The divider has 2 rectangular gold patches.
The resistance between the terminals (about 500 Ohm at rest) is very
sensitive to pressing the foil.
One had a very old handwritten label that I just now could decipher to =
be
"spareparts for micro for loudhailer"
I couldn't imagine this was a microphone cell... till now. I will try a=
nd
hear what sound this can produce one of these days...
It's marked on the back
Technical & Research Processes Ltd. London
A.P.W. 2045
W.D.CAT:
N=B0 Z.B/M.94.0002

Patrick

That sounds like a carbon mic element.
Needs a bit of DC current applied to operate. JLS

Subject: Battery powered TUBED megaphone
From: "patrick"
Date: 8/1/2003 5:37 PM Central Daylight Time
Message-id:


"John Stewart" schreef in bericht
...


patrick wrote:

"John Stewart" schreef in bericht
...


"t.hoehler" wrote:

Hi group, do any of you old timers, like me ), ever remember seeing
an
electronic megaphone from the 50's that was brown hammertone, named
LOUD
HAILER on the side, used vacuum tubes and A & B batteries? I swear,
my
scoutmaster had one when I was in Troop 4 waaaay back in 1962 or so.
It
had
three tubes, a pair of push pull outputs and a preamp. I think they
were
the
3 volt filament tubes like the ones in the big ol' portables of that
era. It
was not a powerhouse, but as a kid I thought it was the neatest thing.
When
you squeezed the trigger, it took about a second for the tubes to warm
up
before you could use it. As I recall, used two 671/2 volt batteries
and
a
couple of D cells to light the tubes. I would really like to find one
of
these, the solid state Fanons would blow this guy out of the water,
but
this
thing was classy.
Regards,
Tom

Probably a 1J6G dual Triode running Class B driven by a 1H4G.
Mic would be a carbon job something like what is in a Bell handset.
If everything worked you could probably get a dependable 1.5 Watts
after output transformer losses.

Cheers, John Stewart

Tom,

I think I have the microphone cell for a loudhailer.
It is an unusual looking element, a 55mm (2 1/4") diameter by 12mm (1/2")
thick brown backelite disk having 2 terminals on the back. The front is
devided in 2 sections and filled with a black material and sealed with
transparant plastic foil. The divider has 2 rectangular gold patches.
The resistance between the terminals (about 500 Ohm at rest) is very
sensitive to pressing the foil.
One had a very old handwritten label that I just now could decipher to be
"spareparts for micro for loudhailer"
I couldn't imagine this was a microphone cell... till now. I will try and
hear what sound this can produce one of these days...
It's marked on the back
Technical & Research Processes Ltd. London
A.P.W. 2045
W.D.CAT:
N° Z.B/M.94.0002

Patrick

That sounds like a carbon mic element.
Needs a bit of DC current applied to operate. JLS

John,

The weard thing is that the carbon is solid (sintered?), not the usual
powder or flakes I've seen in some of these.

Patrick

Some used the carbon mic with a battery in series directly into a
transformer/speaker horn or a speaker horn with a 200 ohm voice coil directly.
As I remember the mic elements, they were quite robust to handle the current
involved.
Neutrodyne