[Boatanchors] testing 0A2 tubes?

[J Forster]

Hello all, while trying to troubleshoot a possible regulation problem in
a
transmitter, I decided to test my 0A2 tube in my tester which is an
I-177-B military
thingy.  Apparently, the test it can do is limited and they caution that
this is
only a partial test.  However, the results are bizzare! So I thought my
tube was bad
because it tested around 500 (on the scale, however I dont think its
micromhos that
its reading for 0A2 tubes)

It is NOT micromhos. Micromohs is a amps/volt and is a GAIN. two element
tubes don't have 'gain'. What the tester indicates is some voltage
parameter with unknown scale factor.

but the needle would bounce around terribly while
pressing the "GAS 1" button.

The GAS test introduces a resistor in series with the grid lead. You
look for a plate current change as a grid resistor is inserted or
removed. The 0A2 has no grid.

[snip]

What does it all mean? Is stability of the needle something that is good
or
indifferent? The manual says >200 is good, but is 1000 better than 200
or is a tube
like this either good or bad with no in between?

They can go noisy or fail to fire at all.

Is there a better way to test these things? Should I throw out this tube
tester and
get something "better?"

thanks
Eugene

Try looking at the voltage in circuit where it will be used with a DMM
for voltage and scope for noise.

-John