ARIA AG20 AMP Schematic NEEDED!

[colmax]

I have an ARIA AG20 AMP that is not working and I'm looking for a schematic. Does anyone have the schematic or knows where abouts to get one? Thanks in advance.

[Jazz P Bass]

Aria AG20R

I have one on the bench at the moment.
No schemeatic on my end.
This amp has a very low hum I can't seem to fix.
The output IC is a TDA 2040.
Pretty easy amp if you want to just trace it out.

[colmax]

I have one on the bench at the moment.
No schemeatic on my end.
This amp has a very low hum I can't seem to fix.
The output IC is a TDA 2050.
Pretty easy amp if you want to just trace it out.

If you are sure that the IC is working then:
1. Check the input jack - it often doesn't work
2. Check power capacitor and diode

Make sure you clean every potencimetar with contact spray. I hope this helps.

[Jazz P Bass]

Aria AG20R

The amp came in for new jacks.
I think this thing took a roll.
IEC connector broken, input jack broken.
Fixed those & the amp hummed!
Changed out the filter caps & the output IC.
Diodes are fine.
The hum seemed to be radiating.
If I probed the ground buss, that lessened it.
WTF.
I removed the reverb IC & the hum was gone.
New IC, still hums.
So I started looking at the ground buss layout.
The ground loops all the way around the board in a "U" shape, terminating at the reverb pot.
I added a jumper to connect the loop & the hum is gone.
It also looks like the reverb circuit could have been laid out a lot cleaner.