hifi engine

Sanyo m1990f

I have a old Sanyo 1990f, would like to request a service manual or schematic.
I'm thinking theres an amplifier issue, sound output is non-existent in the speakers and minimal out of headphones.

Thanks!



Re: Sanyo m1990f

Your protection relay contacts may be dirty.

Re: Sanyo m1990f

Thanks, I'm not experienced with radios could you please point out where that might be.
I inspected the back of two boards can't see anything wrong.

see image: https://ibb.co/gyUBAq

Re: Sanyo m1990f

Kindly , can you upload an image for the connections on the main board
thank you in advance

Re: Sanyo m1990f

If you are not experienced with electronics repairs then it may be wise to take it to a tech. The relay would have to be removed and taken apart for cleaning (if that is the problem); it could be several other things going bad. The protection relay is often on the audio output board, but not always.

Re: Sanyo m1990f

I have experience with electronics and can solder/desolder, but I have no experience with radios specifically. Especially older units, I was a bit surprised once I had a look inside of how things were manufactured back then.
If someone could point out the contact relay it would help, is it the clear module with 1601 written on it?

I'll seek repair quotes in parallel.

Thanks

Re: Sanyo m1990f

It could be the earphone jack itself. Try spraying a little amount of Deoxit (or similar) and some exercise by plugin and unplugin the earphone jack (for helping Deoxit work) about one or two dozen times.