[Central-Electronics] WTB: 6DZ7 tubes and 6L6/6550 Information

[Jim candela]

>
> 	Hi Group,
>
> 	I am looking for some 6DZ7 tubes. These are dual pentodes in a 6L6-GC
size
> package (octal). Each pentode is similar to a EL84/6BQ5. This is because I
> am restoring some tube type audio gear that originally used 7591's as
output
> tubes. The problem is I used most of my 7591's in my collection of Central
> Electronic 20a's as a class Ab1 RF linear amplifier (~ 55 watts pep output
> from a pair, and > 10 watts AM). I converted one Fisher X-101=B amp over
> from 4- 7591's to two 6DZ7's, and that came out working wonderful. I was
> surprised. I need some spare 6DZ7's and I was hoping to find a pile of NOS
> 6DZ7's for ~ $5.00 each. I would also like to win the state lottery too!
> Anybody out there with some of these odd tubes that don't know what to do
> with them?
>
> 	Btw, 6DZ7's were made by GE, and they never seemed to take off in
> commercial gear. Sylvania made a similar tube, the 6DY7 that appears to be
> closer to two 6AQ5's in a single envelope. Anybody know the history of
these
> tubes?
>
>
> 	Here is a application note about 6DZ7's used as AM Ham modulators:
>
> http://www.triodeel.com/ham1.gif
>
> http://www.triodeel.com/ham2.gif


	Notice the application (ham2.gif) note about the 6L6GC from GE that with a
special plate structure was dissipating 80 watts of heat without a
concentrated hot spot. I wonder about the new 6550's made for audiophiles,
and if they use a single alloy, or 5 ply plate structure like GE did on the
6L6-GC. Anybody want to do the test with their 100v/200v's to see if your
brand of 6550 has the single, or multi-ply plate structure? :)
>
> Regards,
> Jim Candela
> WD5JKO