Yamaha emx212s problem

[Michelelynnnusic]

I have a yamaha head that I have had for a few years. Recently I have been having power problems. Wouldn't power up yesterday but today it turned on no problem. I checked the chord. I switched outlets. It has not been dropped at all. Bumped a few times but I don't know if something is loose or if there is a tube that needs replaced. Though I don't believe it has tubes. Used to have a spot on the back of my old head but this one doesn't seem to have them.

[TomCarlos]

Hi Michele...

Unfortunately, the only way to diagnose this problem is to have the unit in a "not working" mode.

The EMX212 is a solid state unit, so no tubes. If you have a situation where there is no power, you do the typical tests -

Make sure the power outlet is working.
Make sure the chord is not bad (usually at the plug end).
Make sure the switch is working properly (do you hear it "click" when you flip it on)?
Make sure the fuse(s) inside the unit are good (and clean, no debris, rust, etc).
Make sure no loose wires on the AC line, going to the fuse, switch, etc.

This would be step 1. After that, you'd need to do some additional diagnosing.

Tom

[Jazz P Bass]

Tech time.

These amps are not fun to work on.

Nor are they anything close to being simple.

The power supply is a switch mode type, so if you do take it to a tech, ask them if they are familiar with these units.