[R-390] R390 progress 6AK5/6AJ5

[Flowertime01 at wmconnect.com]

Cecil,

I do not even find the 6AJ5 in my RCA tube book.
There could be enough difference so that in the actual R390 circuit they may 
not operate as well. Then again the could perform even better. 

I try not to bank to much on my tube tester.

Put one in the R390 measure your signal to noise.
Swap the tube and repeat the measurement.
Find the best one for signal to noise and put them in the other sockets.
Swap the exchanged tubes into the same socket and measure them.
Run the best ones you find of any given tube type.

Do not bank that some tube number does not work as well as another tube 
number.
Your small set of tubes may come from one manufacture, all be old, all be 
noisy all be really hot and you will never get some like them again.

In a message dated 5/2/05 9:14:27 PM Eastern Daylight Time, 
chacuff at cableone.net writes:


> I tested the 6AJ5's in an R-390 that's on the bench as part of testing all 
> the tubes and they all three tested low...not sure they are really bad since 
> they all tested the same....My sub book does not indicate the 6AK5 to be a 
> substitute for the AJ...they look a lot alike though!
> 
> Cecil...