Hi, Now I've retired, I've been trying to (re)learn electronics - I had five years at tech college and Polytech 40 years ago and as things became more "swap and send off for repair" in my line of work (telecoms) my knowledge has degraded. To that end I bought a faulty JVC JA-S11 amp for pennies. I've solved some of the problems but I'm left with distortion on the RH channel (The relevant part of the schematic is attached). Basically if I put my scope on the output of the protection relay (Marked with a red X), I can see the tone is lower than the LH and is distorted. If I stick my probe on the output fuse (FS602 marked red OK)) it doesn't appear to be distored. Do you think the protection circuit could be causing this or am I barking up the wrong tree? Thanks in advance.
Attachments
Could be bad/corroded relay contacts. There are ways to try to clean the contacts using deOxit D5,
but if you can easily get a new part, I would just replace both. Your troubleshooting skills still seem to be good.
Relay part number esk1d24-216
If you have to substitute, the coil is 24V.
but if you can easily get a new part, I would just replace both. Your troubleshooting skills still seem to be good.
Relay part number esk1d24-216
If you have to substitute, the coil is 24V.
Try with your probe to pinpoint the very spot where the signal becomes distorted: R628, R752, the common node of RY701.
If all ok, then rayma is right.
If all ok, then rayma is right.
Or just probe the two right channel audio terminals on the relay itself.
If it's in a socket, that could be corroded or dirty as well.
Contacts can be cleaned with deOxit D and a lintless cleaning cloth.
If it's in a socket, that could be corroded or dirty as well.
Contacts can be cleaned with deOxit D and a lintless cleaning cloth.