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Head-Fi - Alien DAC Construction Thread
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Either that or there is a short.
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If your amp has "DC protection" (i.e. input caps), you don't need output caps on the DAC. As for what could have happened, open it up and take a look - see if there are any disconnected wires or shorts, then take your DMM and check if the PCM is outputting voltage on the signal pins (before the output caps).
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5V reg is in no way dependent on 3.3V reg. If 3.3V is OK, your 5V is doing something funky. Just check on the input and output of that reg to check proper voltage. First though, check that it's installed properly in the correct direction and without solder bridges or cold joints. Check if it gets hot as well.
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Are you kidding me!? Digikey.ca
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Pretty much whatever. I'd use a 1/4W metal film as the rest of the map, maybe 1/8W Dale for simplicity.
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Well, you definitely have a few cold solder joints around, the ones that look dull, not shiny should be reflown. As for 0V off the other channel, you're measuring from the DAC pin to ground right? If this is the case, your PCM is likely fried, happened to me a couple of times before, usually when you apply power to it while it has a solder bridge. If that's…
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Yes, drop the microscope, flood the SOICs with solder and clean up with desoldering braid. Takes about 30 seconds to do the PCM, safest and easiest way I found. I don't care much for solder or chemical cleaners, but do use a toothbrush and 90%+ alcohol. Some compressed air afterwards leaves it nice and clean.
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Clean up the flux and take another photo You also seem to have some questionable solder joints on the back.
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Double check the soldering on the 3.3V regulator and make sure it's oriented properly.
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Considering that there is no such thing as a "lock" in terms of the receiver chips, you don't have to worry. The chip acts as a USB host (sound card) and sends the signal to itself (only supporting 44.1kHz or 48kHz), so it never has to "lock" with another component.