6922 tube testing

[tube-a-lou]

Hi,
I have a few 6922 and want to test them on my Jackson 648 tube tester,
what setting should I use?

Thank you

 

[arts]

Same setting as listed for a 6DJ8.

 

[peguinpower]

Same setting as listed for a 6DJ8.

On my tester, a B&K 707, they are tested differently. Ive always wondered why.

 

[tube-a-lou]

Thank you

 

[arts]

Most of the available 648 test information states testing the 6922 as a 6DJ8, which is close enough for most applications.

The only real differences between the types is that the 6922 has ruggedized construction, longer life expectancy and (some) slightly higher or lower ratings.

I decided to check a little further, as I do have a later-version roll chart for my 648S, and this chart does indeed show different settings for the two types. The two settings provide the same plate and screen voltages, but provide different values for the meter shunt and the plate load. The 6922 setting pushes more current through the tube. Testing several tubes showed no differences in the readings, but the tubes I was using were brand new. The differences may show up when testing used or weak tubes.
Apologies for not being more concise from the start; not a lot of free time these days




6DJ8:
6.3V 123 A45 18XY
6.3V 127 A89 18XY


6922:
6.3V 123 A45 42Y
6.3V 127 A89 42Y

EDIT: for whatever reason, the system does not allow for nice neat columns or tables.

 

[larryderouin]

Add periods between columns (more than 2 spaces)

6DJ8:
6.3V.....123...... A45...... 18XY
6.3V.....127...... A89...... 18XY


6922:
6.3V..... 123..... A45...... 42Y
6.3V..... 127..... A89...... 42Y

 

[tube-a-lou]

Thank you for the new info, I'll will test them out.

 

[arts]

Which model 648 do you have?