Hey all,

Nice to see that after my 7 year absense the congeniality factor here is
unchanged g.

For years, I have been noticing in my RCA tt-4 a tube designated 5556. The
specs for same make me really want to have a go at this one, but I have
never seen one for sale anywhere, and am beginning to wonder if it was ever
even produced.

Anyone seen one of these critters?

DW

On Mon, 28 Mar 2005 16:44:10 +0000, d
wrote:

Hey all,

Nice to see that after my 7 year absense the congeniality factor here is
unchanged g.

For years, I have been noticing in my RCA tt-4 a tube designated 5556. The
specs for same make me really want to have a go at this one, but I have
never seen one for sale anywhere, and am beginning to wonder if it was ever
even produced.

Anyone seen one of these critters?



Welcome back!

http://tdsl.duncanamps.com/show.php?des=5556 look familiar?

Nope, I've never seen one... Looks like it may have been a U.S. of A
"tube" and not one of our proper valves. ;-)

--
Mick
(no M$ software on here... :-) )
Web: http://www.nascom.info
Web: http://projectedsound.tk

mick wrote in
news
Welcome back!

http://tdsl.duncanamps.com/show.php?des=5556 look familiar?

Nope, I've never seen one... Looks like it may have been a U.S. of A
"tube" and not one of our proper valves. ;-)


Mick,

Thanks, and...all too familiar.

DW

d wrote:
Hey all,

Nice to see that after my 7 year absense the congeniality factor here is
unchanged g.

For years, I have been noticing in my RCA tt-4 a tube designated 5556. The
specs for same make me really want to have a go at this one, but I have
never seen one for sale anywhere, and am beginning to wonder if it was ever
even produced.

Anyone seen one of these critters?

DW


I have one of these in my collection. A neat little triode originally
developed by GE for railroad signalling applications. Sold by GE under
the designation "PJ-8".

Unfortunately, the filament in my sample is open... But they WERE
produced.


73,
Bob Weiss N2IXK

Bob Weiss wrote in
news:28o2e.39665$FB6.908@trndny09:

Thanks Bob, Perhaps I'll start looking for PJ-8's.

DW



I have one of these in my collection. A neat little triode originally
developed by GE for railroad signalling applications. Sold by GE under
the designation "PJ-8".

Unfortunately, the filament in my sample is open... But they WERE
produced.


73,
Bob Weiss N2IXK

PJ-8s or 5556s are going to be pretty tough to find through the usual
electronic surplus sources, as they had a limited demand, and
consequent limited production. Just about the only equipment that used
them was old railroad signalling gear, so you might want to try
searching RR-related sites. I got mine in a bunch of old tubes that
came out of the garage of a retired railroad electrician.

GE referred to the PJ-8 and other early vacuum triodes as "pliotrons".
There is a picture of one and a discussion of it's characteristics at:

http://www.du.edu/~etuttle/electron/elect27.htm#Plio

73,
Bob Weiss N2IXK

"Bob Weiss" wrote in news:1112205495.421293.264820
@g14g2000cwa.googlegroups.com:

http://www.du.edu/~etuttle/electron/elect27.htm#Plio

Thanks for the info Bob, Perhaps I'll just have to drop back 15 yards and
punt.

DW