PMX1002D-USB and learning Spanish!

[drewl]

While researching this low budget powered mixer to fix, the only info I found was from a site in Spanish.

I was able to figure out that the 15v regulator goes bad on these, not hard to find but I also found some really in depth videos in Spanish
for fixing my washing machine last month when the lid safety latch switch went bad.


Anyway, replaced the 15v reg with another 1 amp one, but it's getting pretty hot.
The 15v line on the main board a lower resistance to ground than the neg 15v line, possibly because it powers the USB circuit.

I put a meter in series and it's only drawing about 250ma, with no ripple.
The 22v input to the 15v reg has a little bit of ripple, more than the neg 22v line that feeds the neg 15v regulator.


So, I replace those filter caps and see if it helps.

It's a pretty standard power supply, like you'd find in any typical Peavey or similar old school gear.

[J M Fahey]

Well, it´s dissipating almost 2W, which will certainly heat it up.
Post a closeup picture, maybe you can add a small heatsink to cool it.

As of the Spanish videos, link them here.

[drewl]

It already has a heatsink soldered to a ground plane.

After replacing the regulator and filter caps it still gets hot, ran it for a few hours and it was still stable and working okay.