Gorilla GB-30 Bass Combo Power Supply Issue

[misterc57]

Have a GB-30 that will not stay on. Usually it does not turn on, occasionally it is on for a moment (couple of seconds) and then shuts off. Fuse is always good. On/Off switch is always good.

Trying to find schematic to follow PS path. I noticed that the power transformer was sitting loose. I had snugged it up, thought that may be related to problem, loosened it again, no difference in behavior.

The power transformer connectors on the board feel loose, I have cleaned them and I have wiggled them around, no response. I have moved many components with a chopstick, no response.

As always thank you for help and suggestions!

MC

[olddawg]

Do you own and know how to use a multimeter? First thing to do is to see if you have a a DC voltage with reference to chassis ground on the main filter caps. If not work backwards. Check for AC voltage on the primary secondary. Also take an ohm reading across your power cord plug. You could simply have a bad cord, plug, or switch.

[misterc57]

Thank you for the guidance. Looks like one side of the ac cord is bad with very high resistance. I will replace the cord and I think this will resolve the issue. Will report back.

MC

[olddawg]

Thank you for the guidance. Looks like one side of the ac cord is bad with very high resistance. I will replace the cord and I think this will resolve the issue. Will report back.

MC

I would take a resistance reading across the power switch, turning it on and off (with the unit unplugged of course) before you replace the cord.

[olddawg]

Btw.. I actually have one of those amps in my home studio. I put a 12" JBL I had laying around years ago. It sounds great. It's also a very simple amp.

[misterc57]

I did replace the cord. All seems well now. Thank you!