Help, new capacitors bulging within a matter of days!

[rayma]

Probably the entire production run, maybe hundreds.

 

[rayma]

I'm so happy and excited. Thanks all for your help

And now instead of having to buy another board, you have a nice DVM to use in the future.

 

[mjona]

The multimeter arrived..!! And the reading on BOTH capacitors were about -3.1V with DAC powered on ! I did not measure while the music was playing though, and I could not ground the board to chassis while measuring. Note: I measured the 470uf/50V capacitors which I had soldered in, not the empty pads.

I made sure I got the red/black probes right, and even tested with the 1.5V battery to make sure - with the reading coming out at +1.2 or +1.3V.

So, the PCB must have the misprint..!? I am surprised that the music had been playing beautifully and the op-amps, DAC chip etc. seemed to be fully functional without burning out, etc.

I guess this means I don't really need to go out there and buy bipolar caps, and just go back to the original spec of 470uf/25V and I should be set, correct...? I just need to solder it "backwards"..... ?

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The first image shows you have have reversed the cap orientations. These now align with the symbol on the pcb it has taken 3 attempts to get this right which is not a fault with the products supplied.

You managed to get this right with other polarised caps on the pcb there is a small blue cap nearby where there is a clue to correct orientation.. When things go wrong it is best not to panic - you could have asked yourself earlier, what was different to these others.