> Quincy, were you able to fix your clock? It may be helpful to make a little 
> video and post it on YouTube so that we get a better idea of how it's 
> failing. Also, try it with and without the GPS plugged in, and try reseating 
> the MCU as suggested. Also take some close up pictures of the circuit board 
> (front and back) so we can check if anything looks suspicious.

I've been working on Quincy's clock.  I saw some serious squegging in the high 
voltage power supply, and its switching MOSFET was overheating badly.  The 
filter capacitor was also warm.  I tried powering the HV from a Tayloredge 
supply, and it looks better but a couple of digits are still misbehaving 
(blurry, more than one cathode lit at a time).  I hooked an oscilloscope to the 
clock and data inputs to the HV5530 driver chips.  The clock signal is nice and 
clean, but the data signal has a bizarre triangle wave on it.  I don't know if 
it's AC coupled in order to adapt the PIC logic threshold to the HV5530 or 
what, I still need to trace out that circuitry.  The 12V power looks fine 
(there's a small amount of ripple on it, but nothing objectionable), and the 5V 
power is clean.

- John

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