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Tube Testing: Is Measuring Plate Current Important

I am new to tubes and shopping for a tube tester.

The Hickok units seem to be popular, but criticized by some for lacking the ability to measure plate current.

What is the benefit of measuring plate current? If its critical then its odd that a leading name like Hickok would exclude it, especially from military testers where lives could be at stake?

Is plate current related to matching tubes or to tube life? If it's for matching, and PrimaLuna Dialogue 2 has an auto-bias feature that eliminates the problems caused by differences between tubes, will I be a happy camper with a Hickok TV-7 and oblivious to plate current measurements?
128x128androux
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bob_bundus
1,834 posts
 
does the tv7 measure voltage gain? Isn't that the whole point of testing? Perhaps it is indirectly displaying Ip by way of the gain calculation?
atmasphere's avatar
atmasphere
7,068 posts
 
The Hickoks are good testers. Usually you don't need plate current to test the tube, but you should understand that tube testers like the Hickoks, which are called transconductance testers are in fact an approximation. But they are usually much more accurate than emissions testers, which are usually a lot cheaper, although they can test the tube faster.

There are testers that do apply plate voltage, like the old RCA WT-100, but expect to pay a pretty penny for one of those, in good operable condition they can be $1000-$2000. They are also quite large...

So the Hickoks are a very good compromise.
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