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10000uf?  oh, missed that last zero.

that should be plenty, you could just stick in a couple new ones of that
value and it should be fine.  don't think they need to be larger.

 
15000uf  should be cool,  it's kinda what i've was thinkin'

Mouser of Digikey would be the first places i would look

got a caliper for measuring hole spacing?
 
Trying to find information about the diods 5-8 on the shematic iss133t-77 mounted between the two transistors, top right on the schematic, someone knows anything about them ?

power_supply_unit.jpg
 
Kir_For_Pleasure said:
Trying to find information about the diods 5-8 on the shematic iss133t-77 mounted between the two transistors, top right on the schematic, someone knows anything about them ?

They lift the ground pins of the 7815 and 7915 regulators a couple of diode drops above and below (respectively) ground, so the outputs are a bit over ±16V instead of the expected ±15V.

-a
 
In addition to what Andy said, there were some early 3 terminal regulators that could latch up at turn on if the wrong rail came up first. More of a problem with half wave rectification, and IIRC only one brand of 3 terminal regulator. I had one (very good) engineer working for me who refused to stop adding these diodes to prevent latch up for years after this ceased to be a problem.

Since you only need one diode to prevent the latch up, and this design uses two in series, I will speculate that they are just going for a little higher output.

Note: putting diode junctions in series with the ground leg, degrades the regulation quality, since differences in regulator ground current modulates the forward diode voltage which is effectively in series with output voltage.  This will also increase regulator voltage sensitivity to change with temperature, but most audio circuitry doesn't require perfect regulation, or they wouldn't use 3 terminal regulation in the first place.

JR
 
I need to etch a new board for the old one got cracks..someone have some improvments to share ? would it be complicated to implant a relay based insert bypass...decoupling caps..here is a schematic of the board

StereoMasterPcb.jpg
 

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