Yamaha emx 640 schematic

[dale756]

A transistor BC706 overburned in the circuit and burned a few resistors and I cant see the colors of the rings to read the value of the resistors.
So Ill need the schematic or a picture of the circuit board which is on the backside of the cooler.

Greetings from Croatia!

[The_Hawk]

Three years without a reply? ...I will assume you don't need the requested info any more ... just guessing....

[Enzo]

Well, if we don't have it, we don;t have it.

[mozwell]

i have a copy but its 9M in size, The limit here is 3M i think... ( stand to be corrected)

shoudl be easy enough to google search for it (thats where i got it from)

Lots of Yamaha info here Audio : Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
and on the "professional" sub page
Also on ElektroTanya | Service manuals and repair tips for electronics experts you need to register & answer a few simple electronics questions, but its free & the have a mountain of good info.

[The_Hawk]

Now this is funny. I had posted on another thread that was for the EMX660 powered mixer . this post was just cause I thought it funny no one ever replied to the guy. Thank you for the yamaha links I still need to look at the above mentioned unit's schematic.

[Jazz P Bass]

i have a copy but its 9M in size, The limit here is 3M i think... ( stand corrected.

You can use a free program called Cute PDF Writer.
When you select "print" it will appear as a printer.
You can break down the schematic in pages that will fit the 3m limit.

[The_Hawk]

Due to the fact that this EMX660 looks virtually brand new with no signs of wear, I told the owner's contact that it would require extensive work to trace down the faulty component(s) causing the signal loss at the amplifier stages, so before I go crazy trying to dredge up a schematic for this unit I need to find out if my estimate of repair is approved.

[Enzo]

Why would looking new make it harder to fix than one that had seen some use? Most bad parts don't look any different.

[The_Hawk]

Maybe I phrased that improperly, what I meant was that none of the circuitry showed any signs of any damage having occurred. Usually when a component fails it shows some residual burn out ,blown resistor, scorch marks on the board, cap juice, liquid stains from something being spilled into the unit,and ding in the case might mean it was dropped....etc. in other words I can't see any physical evidence as to why the signal isn't getting to the amp section, my gut tells me it's the transformer but without a schematic I'd be relying on experience as to what the readings I get mean.

A schematic is the road map to help you find your way from the input to the output of an electronic device.
Knowledge is what you get when you use one, experience is what you get when you don't...

[Jazz P Bass]

Maybe I phrased that improperly, what I meant was that none of the circuitry showed any signs of any damage having occurred.

Oh, if only it should be that easy.
Exactly which Yamaha schematic are you after?

[The_Hawk]

Oh, if only it should be that easy.
Exactly which Yamaha schematic are you after?

The EMX660 powered mixer by Yamaha

[mozwell]

EMX 660 is in here Audio Yamaha : Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
EMX 640 is in here Professional yamaha : Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics

lots of other EMX files in both places

[Jazz P Bass]

Yamaha EMX 660 Service Manual

Here you go.
(had to break it up to fit)

[The_Hawk]

WOO HOO! You are the Man ! Thank You !!