Vox AC15 RE keeps blowing fuses

[Bernardduur]

Hey all!

Lately my Vox AC15 (reissue version) keeps blowing fuses. I've read that some of these problems were due to the rectifier tube.

A. As I have no 5Y3 laying around, to test this theory, can I pop in a different rectifier tube? A GZ34 for example (I have some of those laying around).
B. Are there more issues I should take care of or expect to deal with with these amps?

Thanks for the read!

[Garydean]

Replace the fuse and turn on the amp without the rectifier tube in place. If the fuse still blows, the rectifier tube is not the problem. Perhaps one of your output tubes has gone bad.

Remove the output tubes, replace the fuse, and see if the fuse still blows when you power it up with the output tubes out. If it still blows, the tubes are not your problem.

[Bernardduur]

Thanks!

I tried this but still fuse popping

When I measure the PT I get a weird reading:

The main high voltage line has 3 points (one center tap). If I measure the resistance of the transformer taps according to the center tap I get 12 ohm on one side and > 20 Mohm on the other

I guess the PT is fried. Keep on hearing the same stories on the internet

[Garydean]

what you're doing there is measuring half...but not really...of the windings resistance to the centertap, which sounds ok. Can you measure the secondary to see if you are getting the correct reading? OR disconnect the secondaries completely and see if the fuse blows. Check for arching around the tube sockets also.

[Bernardduur]

No arcing

Secondaries all measure good except for 1 (the >20 M ohm).

With the secundaries removed the fuse blows

[Garydean]

"""""Secondaries all measure good except for 1 (the >20 M ohm). """"

I didn't see the M after that >20 before.

[Bernardduur]

Now looking for some new transformers.........