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12AX7/LPS Sovtek - I am very confused, please help

I just purchased a brand new 12AX7. I tested it on some of my emission type tube testers I have, namely:
B&K 606
Sencore; TC-28, TC-162
Eico 625

testing this tube makes the needle move 1/4" off zero, some make the needle go to the middle of the "replace" and then drops down to about 20.

This is a brand new Russian Sovtek 12AX7/LPS, I find it hard to believe it's bad.

I tested a 12AX7 from 1969 and it read very good on all my testers.

I contacted the merchant that sold it to me and he gave me a very long winded story about what is good and bad and he tests them on a Hickok and was leading me to believe all my "emission" tube testers were not checking it correctly.

I told him I can't understand why I can't use a vintage emission tube tester to check this NEW 12AX7.

Is he right? or is the tube very very weak?

Please help me with this.

Thanking in advance.

-TommyR
tommyr
jomik
11 posts
 
I had this happen too and asked Brent Jesse at audiotubes.com about it. On b&k testers including the 606, a new 12ax7 will test at 25%.
mechans
3,048 posts
 
It sounds like a simple dud. I hear from experienced dealers of new tubes that about 5% of them are rejects if Russian.
I agree check it by using it but check it for shorts first
tommyr OP
1 posts
 
hmmmmm, my new Grove-Tube 12AX7 comes up to 25% on my b&k 606 but the 12AX7/LPS Sovtek barely moves the needle.

-TommyR
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