Mesa 50/50 Ch. A very low output

[JustMike]

 This amp is an earlier rev than the one in the schematics library. Mine doesn't have a choke for one. I've got good +VDC at node C (450v) , but at the plate on the other side of R282 (82k), I've got 126v and the schemo shows 316v.
 Any ideas?

[shooter]

what's happing on the other plate?

[tubenit]

Do you have a 12AX7 or some other 12A_7 in that position? 

[PRR]

what's happing on the other plate?

And the common cathode?

Diagnosis by checking just one point in a circuit with more than two parts requires brilliance or great luck.

[Keppy]

If you need a schem, try contacting this poster. It looks like he hasn't been active in about 6mos, so DM me if you really need it and can't reach him through the forum.

[Latole]

Remove V2 ; how many volts ? Did you get the 316 V ?

[JustMike]

Thanks all. It was a bad P.I. tube. BUT the owner just told me that originally the amp was redplating. He replaced the 4 output tubes and then noticed that channel A was not working. So now I have to monitor for redplating.