What's Up With the 6DJ8?
 

I got a dozen used Bugle Boy 6DJ8s here.
On my TV-7, the same triode (first one) of the pair
within each tube tests low emission. The other one test fine.
This seems pretty suspicious...
The updates and corrections for the TV-7 don't deal with the 6DJ8.
Is this a common thing with the 6DJ8, or is my TV-7 to blame?
Thanks.

Hi David,

I have not seen that kind of regularity in the dozens of
6DJ8 tubes that I have tested.

I would bet it is a problem with *your* TV-7 tube tester.
I would suggest that you try testing some of the problematic
6DJ8 tubes on some other tester.

Barring that, you can manually connect a 6DJ8 to your
tube tester using clip-leads and short chunks of wire, and
test each individual section using the same setting on the
tester. (eg. use section 1 settings to test both section
1 and section 2.)

If you don't have another tester to check against, you
can always mail one of the offending tubes to me, and I will
check it for you.

-Chuck

David Stinson wrote:

I got a dozen used Bugle Boy 6DJ8s here.
On my TV-7, the same triode (first one) of the pair
within each tube tests low emission. The other one test fine.
This seems pretty suspicious...
The updates and corrections for the TV-7 don't deal with the 6DJ8.
Is this a common thing with the 6DJ8, or is my TV-7 to blame?
Thanks.

It's possible they were in an application that was particularly demanding on
one section or the factory had a bad batch. Look at the date codes and
confirm that the TV7 is OK
hank wd5jfr
"David Stinson" wrote in message
...


I got a dozen used Bugle Boy 6DJ8s here.
On my TV-7, the same triode (first one) of the pair
within each tube tests low emission. The other one test fine.
This seems pretty suspicious...
The updates and corrections for the TV-7 don't deal with the 6DJ8.
Is this a common thing with the 6DJ8, or is my TV-7 to blame?
Thanks.

Henry Kolesnik wrote:
It's possible they were in an application that was particularly demanding on
one section or the factory had a bad batch. Look at the date codes and
confirm that the TV7 is OK

The Tektronix 6DJ8s from AES are cheap and measure perfectly on my curve
tracer. If you need a reference unit, order one of them.

Does anyone know if the 6DJ8 is still in production? Is it recommended
for new designs or am I better off using a 12AX7 series tube and living
with the high input capacitance?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey wrote:


Does anyone know if the 6DJ8 is still in production?

I don't think the 6DJ8 is produced anymore, but Sovtek (New Sensor)
sells a 6922, which is an industrial equivalent.

Bob Weiss N2IXK