Yamaha MX-830 relay sticking open

nguyendot

Picked up this amp cheap, but it seems the delay relay doesn't click closed unless I tap it. I see it trying to close, it buzzes and the contacts move trying to, but they don't move far enough.

What could cause this? Bad relay? What can I do to remedy it? It plays fine and clean if the circuit closes.

thanks

WilliamM2

Could be the relay. It could also be the circuit that supplies the voltage to close the relay. I had that happen on a Parasound, it needed 12 volts, but was only getting anout 8. Sometimes it would close, sometimes not. Can't remember what the part was, it was either a small cap or a diode. I do remember that it only cost 35 cents for the part.

nguyendot

That sounds logical. If I open the relay and tap the magnetic lever down it holds, but it's not strong enough to pull itself. Either the relay is bad, or it's not getting the right voltage. I'm guessing the latter.

nguyendot

I think the relay isn't getting the right voltage. The metal pan doesn't pull down hard enough. There's a diode RIGHT next to it. What should I check?

WilliamM2

Check the voltage going to the relay. You need to know what it's supposed to be. Should be printed on the relay housing. As far as testing the components if it's not getting enough voltage, most can't be measured in circuit, you will have to remove them and test one at a time.