Mackie SRM450

[goldtop5]

Does anyone have a schematic for a Mackie SRM450 ver. 2?

[Jazz P Bass]

Mackie SRM450 V2 Schematic

Here you go.
Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics

[goldtop5]

Thanks!

[MarkusBass]

Can anyone tell me what is the U36 IC in Mackie SRM450V2 (SMPS version)? I've got one with exploded U36. It looks like PCF controller but what is the symbol? It seems that exactly this information is missing in the SM

Mark

[paleeman]

Hi Mark

It is UC3842.

[paleeman]

Have the Loud's version of the schematic, too.

0029446-XX-H00-SCH.pdf

[MarkusBass]

Thanks. The Loud version seems to be much more precise.

Mark

[MarkusBass]

Here is a photo of the PC board. It seems it was repaired previously (because of the same reason - failed PCF circuit). I found out that the core of the PCF coil is loose. Can this be a reason for the failure? The core can be moved about 2 mm. I assume that the core shouldn't move. Maybe it was glued initially?



Mark

[paleeman]

Hi Mark. That is not the PFC coil, it is the line filter. But, still, it shouldn't be loose. I'd definitely glue it back.

[chromatest]

I've got a couple of these, with damage in the same area.

My hypothesis is that the ferrite bead/choke that is on the cables going to the speakers gets loose and when you move the speaker around (especially when it has power applied) it bangs against things shorting them out, or at least physically bashing the components apart.