Sansui 771 replacement relay

EastPoint

Recycler
Subscriber
Hi folks. Does Mouser have a relay for the 771? I couldn't find anything in the forum. My relay sometimes needs the volume turned up for one channel to kick in, and I figured I should replace it.
 
East Point,
Usually you can remove the relay (may have to desolder). Then the clear plastic cover comes off easily. Remove the small spring on top and you can get to the stationary contacts as well as the contacts on the pivot arm. I use a pencil eraser to remove the tarnish on both the stationary and pivot arm contacts. I have an eraser that I cut in strips so that I can clean the stationary contacts easier. When finished I wet the contacts with deoxit gold G5, and blow off excess with can of air. I put the pivot arm back in place and reinsall the spring. If the pivot contacts look as they have bent a bit, and just barely make contact when you press the relay pivot down, I remove the spring and lift out the pivot arm out again, and slightly bend the contacts, so that when reassembled with the spring in place, you can see that the contact arm bends just a little as you press down on the pivot arm at the end of travel. This is needed to "Wipe the contacts" every time they close. I use a digital meter to make sure the contacts (Pivot arm to N/O contacts) measure less than 0.3 ohms when the pivot arm is pressed down. I also check that the N/C contacts (If the relay has them) measure very close to zero ohms as well. If the eraser didn't work well and you have more resistance with the contacts due to pitting, you may need to use a relay contact burnishing tool to better clean the contacts. I only use that when all else fails because it can remove the plating (gold or Silver) on the contacts.
Reinstall the relay (without the cover), and power up the unit. Verify that your DC balance is close to 0 volts because DC on the contacts can cause arching and pitting of the relay contacts.
If everything is fine put the clear plastic cover back on. Be careful as the covers only go on one way (the cutout on the back of the cover goes on the relay coil side.

But if that doesn't work and you want a new on, mouser has them
MY2-02-DC24 (Omron Relay)
 
Back
Top Bottom