Acoustic amplification ag60 - loud hum

[buck1108]

I am working on an acoustic amplification ag60 amplifier. I was told that it quit working after a nearby lightning strike. This amplifier is making a loud humming noise and there is no audio signal from the input coming out of the speakers. However, there is a mix of a hum and audio input coming from the headphone jack which is an output from the preamp section. I have replaced the power transistor chip in this with no change in the situation.

I'm continuing to test this, and so I decided to start by testing the transformer.
I disconnected all primary and secondary connections from the board and did a continuity test. There are 3 secondaries on the transformer and each of the three tested with 100% continuity between each of the secondaries' leads. The thing I wonder about is that one of the secondaries also tested continuity with another set of secondaries.
More specifically there is a pair of yellow wires, a pair of orange wires, and three wires consisting of two reds and a green and the middle. The three wires tested continuity with the orange wires.
Could this be in the design, or is this a flaw or damage?

Thanks

 

[Binkman]

Greetings;
the only thing I come up with is this link for a guitar amp. Is this it? or do you have a reference link?
http://www.prowessamplifiers.com/sc...rAmp-Acoustic_G60_212_PowerAmp_Schematic.html

 

[buck1108]

Greetings;
the only thing I come up with is this link for a guitar amp. Is this it? or do you have a reference link?
http://www.prowessamplifiers.com/sc...rAmp-Acoustic_G60_212_PowerAmp_Schematic.html

Thanks for your post.
It is this amp: https://acousticamplification.com/ag60-acoustic-guitar-combo/

The AG60 is different from the G60, which is an older amp.

 

[buck1108]

Here's a photo showing the power board (top center) with the secondaries (yellow, orange, red/green).

 

[Binkman]

edit:
Your first link Well no help there and your https://www.diyaudio.com/forums/sol...-amplification-ag60-guitar-amp-schematic.html
so still looking for help.
------
Without a schematic (can't find anything) with continuity on the transformer on A and secondary probably okay, the surge was fuse protected on the transformer. I'm guessing a lot..okay?
Is the Hum affected by vol.?
And a associated pics from the p.s. would be helpful to see what members are looking at.

 

[buck1108]

Thanks.
The hum does increase with the volume increase.

 

[Binkman]

Only three clues is audio and hum through the headphones and only hum from the speaker and hum is affected by Vol. is audio signal path related. ((with all that excessive cap adhesive how can you tell if somebody didn't put a cap in backwards.))
We're flying blind without a schematic or serv. manual. Have you contacted Acoustic?
https://acousticamplification.com/contact-us/