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Help with amp, Please?

Hey everybody,
I recently got this little Fender Frontman 15R project from a nice fellow that had an ad in Craigslist. Free. Sweet! He told me it wouldn't come on and that he had poked around looking for an obvious short, but didn't really have the knowledge nor resources to thoroughly inspect it.

Since I know just about enough about electronics to get me into trouble, and I had just purchased a multi-meter, I brought it home and took the amp apart. Now I have been studying on how to make low-power LM386 style amps for a few months, but have yet to start a project.

Once I got it home I plugged it in and as expected, I got no "On" light and no sound whatsoever.

I got the back off it, I poked around inside and wiggled a few wires, but didn't see anything. I put the back back on and plugged it in, turned it on and the light came on, and normal-sounding hum came from the speaker. Plugged one of my guitars in and got nothing but hum. So, off came the handle and the rest of the hardware necessary to pull the circuit board stuff out. As I was checking the wire connectors on the on/off switch, the ground wire just popped out of the connector. I don't know, but suspect that this amp has been messed with inside since sold new. The bare wire was less than 1/8 in long when crimped. No wire was left in the half-crimped connector. So I replaced the connector with a new one. As I was taking one last look inside and getting it ready to button back together for a test run, I found this:

The chip in the circuit board (Upper right) and the solder on the metal cover.

From the other side:

So, is this silly looking wad of solder on the cover of the jack from the factory, or someone needing to ground the already broken board? I would like to get everyone's suggestions on how to best go about fixing this thing. Scrape to bare copper and try to wire in a conventional jack, or something else? I have very little money to put into this thing, so I might wind up scrapping it and just using the pots and other bits for home-made cigar box amps. The only other amp I have is a Micro-Cube, (Love it!) My soldering skills are fair to good. I really don't want to scrap it since it is in otherwise very good shape. What would YOU do? Would you fix it, and if so, how would you fix it?

Any suggestions would be VERY much appreciated.

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Permalink Reply by KOOL DOG HOOCH on April 1, 2020 at 4:39am

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Permalink Reply by Southern Ray on April 1, 2020 at 3:35pm

I'd love to hear what you tried to say, Hooch!

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Permalink Reply by KOOL DOG HOOCH on April 3, 2020 at 9:08am

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Permalink Reply by KOOL DOG HOOCH on April 3, 2020 at 9:09am

I have the 15G, how can I help?

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Permalink Reply by Southern Ray on April 3, 2020 at 9:16am

How do you like the 15G?

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Permalink Reply by Southern Ray on April 3, 2020 at 9:15am

Hi there! You got through. You tried so hard to reach me, I just sent you a "friend" request just trying to give you some method of contact. How are ya?

As far as help on this amp goes, thank you, I think I have a plan to fix it, but I am waiting now to be able to get a soldering tip. I don't have the right one for the fix.

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Permalink Reply by BrianQ. on April 3, 2020 at 9:28am

I remember coming across this video a few years ago, he’s got same problem you do?

https://www.youtube.com/watch?v=RoGR3vmHSlI

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Permalink Reply by Southern Ray on April 3, 2020 at 3:54pm

Thank you BrianQ! It's very close to the same problem, the same guy did this one: https://www.youtube.com/watch?v=F8I_Tyd8JmU that is exactly the problem that I had except my version had the added issue with the heatsink/cover/ground/whattheheckisit on mine.

Thanks again!