Eurodesk MX3282A schematic

[clintronics]

Anyone have schematic for output section from Main Insert jack to main output xlr jack?

[Enzo]

We Behr service centers have to sign a non-disclosure agreement, we specifically cannot share schematics. I can answer most any question though.

If you have a dead master channel it is almost always a bad slider. MAster sliders VR87, 88 are the main L and R out, they are both served by U77, a 4580.

[clintronics]

I have audio at the fader and the insert jack but not at the meter or the output jack

[Enzo]

IS there audio on both the top of the slider AND the wiper? At the output of U77?

I realize it might be hard to find U77, there are no layout drawings in our service documents. Is it tucked between teh sliders? Or is it up above them a few inches?

[jrfrond]

Also be aware that insert jacks are always an issue on these mixers as well, in addition to plain ol' cold solder joints.

[Enzo]

In fact, I have a TRS plug with T and R soldered together inside. I plug it into an insert jack as a bypass. I use it enough it lives in my patch panel on the bench.

[Jam]

What do you mean by I have a TRS plug with T and R soldered together inside and how does that work ? I didnt know you could help with mixers

[clintronics]

Ya I got audio on input and wiper of fader and in and out of the insert jack, got to be a blown ic just after faders but before the meters. IC 76 has no audio. IC 78 does. 76 sits above 78 between the 2 main faders .There is no Right output on this mixer.

[Enzo]

Jam, on a guitar amp we usually have an effects loop - separate send and return jacks. SOmetime when there is a problem we plug a cord from one to the other to act as a sort of bypass. When space is limited, sometines they use one jack and call it an "insert" jack. it is a TRS jack, and the tip is the send and the ring is the return, or maybe the opposite. SO with a special Y cord, the one jack can send and return like an effects loop. Since we cannot plug a cord from send to return in that, I make a special TRS plug where I solder a wire between the Tip and Ring contacts inside. When I plug that into an insert jack, it shorts the send and returns together and thus bypasses faulty normal contacts inside the jack.

I use it for testing only, it has no useful effect on a mixer - well except allowing a channel with a bad insert jack to function through the gig.

My shop works on just about any peice of equipment that is used to make music, not limited to guitar amps. We service everything from a Korg Oasys to a Conn strobe tuner to a 1" tape deck to lighting controllers. But we don't take in Fender Rhodes pianos, I refuse to work on the damn things, or your little Wurlitzers.

[jrfrond]

But we don't take in Fender Rhodes pianos, I refuse to work on the damn things, or your little Wurlitzers.

Ah Rhodes and Wurli's.....we eat 'em for breakfast here in NYC. Seems like everyone has at least one of those (along with Clav's and Mini-Moog's) sitting in their closet somewhere! :eek:

[Enzo]

I figure anyone who tours with one ought to know how to service it himself - since he will need to. They take up half the shop, and I don't want to lift it.

I have tons of the little metal reeds for the Wurlitzers though - sorted even. If they haven't thrown them out yet, I know where there are a bunch of the action parts too. Though those never seem to break. I haven't stocked any Rhodes parts in ten years or more.

We used to service for a school system who had a classroom of 20 of the damned Wurlitzers, and every summer they would truck them all to us for service and pick them up around labor day. Swell, 20 Wurlitzers clogging the shop.