[Username1]

Well, people say you can't go by the tester on those tubes because you
would have to know the unit's current draw, and be able to tell the tester to
show "good" at or above the current the tube is expected to pass......
So to best test the tube in your set, you should check the voltage at the first
filter cap, and see if it matches the sams....
You could cut the line off the cathode and check the current, is it within spec of what
the tube should be able to pass...? Use a scope, is there ripple...? Too much ?

You could cut the circuit out, put a resistive load cathode to ground ans see what the
voltage is with say a 5ma load on it, then put on the rest of the tv, and see if
there is too much drop driving the set.... It would be good to have a known good
5u4 to compare to, but you should be able to get a feeling for what's going on.....

Hum bars, open caps in PS, too much load on ps.

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