Hi. I have a Metro JMP 50 w plexi which I bought seceond hand this summer. It's been working great till it suddenly started to blow the mains fuse, right when I turn it on. Any suggestions: I have tried to change the El84 and the rest of the tubes, but same thing happens?
Best from
Norway.
Blows fuse
Moderator: VelvetGeorge
-
- New Member
- Posts: 16
- Joined: Thu Aug 21, 2014 2:12 pm
- Just the numbers in order: 13492
-
- Senior Member
- Posts: 1407
- Joined: Fri Mar 12, 2010 9:05 pm
- Just the numbers in order: 7
Re: Blows fuse
Did you check the bias, PT?
-
- New Member
- Posts: 16
- Joined: Thu Aug 21, 2014 2:12 pm
- Just the numbers in order: 13492
Re: Blows fuse
Hi and thanks, but I don't know how to do that?
- VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: Blows fuse
Your Metro 50 should have EL34 tubes, not EL84. Please double check that.
To troubleshoot:
Pull the output tubes and replace the fuse. Does it still blow?
Remove the HT fuse. Still blow the mains?
Most common reasons a working amp will start to blow the mains fuse are:
an output tube shorts
a diode in the power supply shorts
george
To troubleshoot:
Pull the output tubes and replace the fuse. Does it still blow?
Remove the HT fuse. Still blow the mains?
Most common reasons a working amp will start to blow the mains fuse are:
an output tube shorts
a diode in the power supply shorts
george
-
- New Member
- Posts: 16
- Joined: Thu Aug 21, 2014 2:12 pm
- Just the numbers in order: 13492
Re: Blows fuse
El34's offcourse, but I'll check testing you suggest.
The two speakeroutputs by the way, are they f x 16ohm when using both or do the change the ohming?
The two speakeroutputs by the way, are they f x 16ohm when using both or do the change the ohming?
-
- New Member
- Posts: 16
- Joined: Thu Aug 21, 2014 2:12 pm
- Just the numbers in order: 13492
Re: Blows fuse
Whatever I do according to your suggestions the fuse blows.