M100 Reapir......again!

[rsweet1]

So i have a M100 that i just got fixed and i am having problems with it again.
Well first, the right channel is producing static. The static doesn't change if i change the volume.
I am assuming this is DC bleeding through somewhere? Anyone know where to start looking?

Secondly, the amp recently started making a faint noise when i power it up. Soon after, the amp completely shuts off.
I guess this is the protection circuitry? Once again i have no idea where I'd look.

The amp has no burnt components, smells, or apparent damage of any kind.
Directing me to anyone who can fix it would be equally appreciated.
Thanks in advance.

[tonym]

So i have a M100 that i just got fixed and i am having problems with it again.
Well first, the right channel is producing static. The static doesn't change if i change the volume.
I am assuming this is DC bleeding through somewhere? Anyone know where to start looking?

Secondly, the amp recently started making a faint noise when i power it up. Soon after, the amp completely shuts off.
I guess this is the protection circuitry? Once again i have no idea where I'd look.

The amp has no burnt components, smells, or apparent damage of any kind.
Directing me to anyone who can fix it would be equally appreciated.
Thanks in advance.

send it to valeks1 ...hes the one who fixed them when PG was still in portland...
He is fast and does GREAT work...

[dvnt88]

So i have a M100 that i just got fixed and i am having problems with it again.
Well first, the right channel is producing static. The static doesn't change if i change the volume.
I am assuming this is DC bleeding through somewhere? Anyone know where to start looking?

Secondly, the amp recently started making a faint noise when i power it up. Soon after, the amp completely shuts off.
I guess this is the protection circuitry? Once again i have no idea where I'd look.

The amp has no burnt components, smells, or apparent damage of any kind.
Directing me to anyone who can fix it would be equally appreciated.
Thanks in advance.

send it to valeks1 ...hes the one who fixed them when PG was still in portland...
He is fast and does GREAT work...

DITTO ...he fixed my TI500.4 and resurrected a ROUTE66 I got off the Boise CL and knows his shit and is fast . All his repairs come with a 90 day warranty , so no worries.

[Eric D]

I assume this is the M100 I worked on a few months ago. If so, did it ever work for you? What speakers did you have connected to it?

Either way, by the sounds of it, one of the output transistors could be damaged. It may be the source of the static you describe, and is now drawing too much current, which caused the transformer to make a whining noise when powered on, then the protection kicks in and shuts down the amp.

One way to be sure would be to put a 10A or 15A fuse on the amp and see if it blows. Try it first with no speakers connected and no RCAs connected. Then try it with just RCAs, then lastly with the speakers connected as well.

[rsweet1]

Well after i got it back, i put it in my truck. I wired 2 4-ohm polk speakers in parallel to each channel, so it was running 2-ohms per channel. It sounded fantastic.....until it suffered blunt force trauma....I was transporting a vacuum cleaner and someone cut me off, so i slammed the brakes on and the vacuum hit the amp....

I pulled the amp out, opened it, and looked it over. I really can't any damage at all. I pulled out the rca, and its still making the noise and static. I don't have any small fuses or fuse holders so i cant exactly test it.

Would you be interested in working on it again, Eric?

[Eric D]

So the amp was struck on the cover of it, or on the terminals?

[rsweet1]

It was struck right in the center of the cover.....but there are no dents or anything...

[The Golden One]

i wonder if maybe the impact could have jarred a connection loose somewhere in the amp possibly in the signal section of the amp maybe that's what is causing the noise. since the amp may have been playing when the impact happened then maybe the jar was enough to cause a back current issue and maybe it fubared your opamps.

[ttocs]

time for technical taps!