Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.

wrote:
Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.

I found regular plain old receiving tubes worked OK down to 18 volts on
the plates - didn't have any convenient way of getting 12 at the time
but I'll bet they would have worked.

Audio power amps had REALLY low output but if you're building a 1-tube
regen you're not driving a speaker anyway...

--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

I think some early Motorola auto radios worked off DC directly and had
tubes in the RF and transistor audio PA's. You might look for some
vintage auto radio schematics for tube numbers. I thing the 12AX7 tube
might be included.

wrote:

Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.




--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

Hi: in this site have good information over space charge mode function in
conventional tubes (no special for 12 v).- This mode permit work the tubes
with low voltagfe in plate.

http://www.duntemann.com/12vtubes/12vtubesindex.htm

In the followings sites have a receiver projetc with 6BA6 tubes working with
12 V in plate.-
http://www.qsl.net/kl7h/GlowBug.htm

http://www.qsl.net/kl7h/12v.htm

REgards from Argentina

Heriberto
LU6DBU


escribió en el mensaje
ups.com...
Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.




Inviato da X-Privat.Org - Registrazione gratuita http://www.x-privat.org/join.php

hI:
I forgoten this site also ;

http://www.oldradios.co.nz/hikers/

Regards

Heriberto
LU6DBU

escribió en el mensaje
ups.com...
Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.




Inviato da X-Privat.Org - Registrazione gratuita http://www.x-privat.org/join.php

Heriberto wrote:
hI:
I forgoten this site also ;

http://www.oldradios.co.nz/hikers/

Regards

Heriberto
LU6DBU

I second this one. I've built 3 Hikers, bcb and sw...one is featured on
the site...and they have been excellent rcvrs for low voltage. The
later version using 3Q5s also works very well.

-Bill

there was a menufacturer here in 4Zulu land who made suck radios. I
think I have the schematic at home: i'll look itup this evening. I
think one of them was 12k7.
Actually I had that readio for years. I can't remember what became of
it.
Saandy 4Z5KS

FYI,

The tubes designed to work on 12 v for the plate might be best, but there
are a number of battery filament tubes that also migh give you some
results. eg. 1L4,1T4,1U4,1R4,1R5, etc (all 7 pin miniatures). (there was a
series of 8 pin octal tubes, too). Most of them ran filament voltages of
1.4 volts at 50 ma current. I built a audio oscilator with a 1T4 (pentode)
as a kid and it would oscilate down to 7 volts on the plate!! Most of those
tubes were designed for up to 90 v on the plate. Power audio tubes were like
3S4, 3Q4, 3A4, etc (which would run 3.0 v at 50 ma, or center taped filament
at 1.4 v and 100 ma). The 3A4, pentode, as RF amplifier was good for
something like 1/2 watt output or so, not bad for QRP and no transistors.

There was an older series of battery fillament tubes, designed for lead
acid cells (all were 2.0 v on filaments and not much amperage, either).
You'll have to consult an older tube manual for those if you want to try
them.

===== no change to below, included for reference and context =====

On Sun, 7 May 2006, wrote:

Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.

ORIGINAL MESSAGE:

On 7 May 2006 14:26:04 -0700, wrote:


Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.

*********** REPLY SEPARATOR ***********

My first job right out of high school in 1959 was repairing car
radios, just when the 12-volt anode tubes were coming out. On a whim,
I replaced some of the 12-volt anode types with conventional tubes
such as the 12AU6 and 12BA6 and to my surprise, they worked fairly
well, but with slightly lower gain. (The pin connections were the
same.)

BTW, the 12-volt anode types were notorious for developing
microphonics. It was an interesting design, but as soon as good
transistors became available, they became history.

In other words, don't be afraid to experiment.

Bill, W6WRT

wrote:

Anybody know any tubes...st or gt shape preferred that will work on 12
volts plate voltage for small 1 tube regens...possibly a stage or two
of amplification also.

I know there were automobile radio tubes made that didnt need vibrators
but dont know any numbers myself.


In desperation, I once wired the triode section of a 6U8 into an
oscillator circuit that had been designed for one of those 12v space
charge tubes. It worked that one time, anyway.

I was replacing a pair of "VHF Triode-Pentode" tubes by Sylvania (I
don't remember the type number) in an FM to AM auto radio converter
whose performance really sucked. The other three stages were fairly
easily re-wired to work off an external 250v supply, but the oscillator
didn't look promising. The effort was a success. I think I at least
tripled the distance from the stations at which I could hear them.

73, CJ KØCJ