Thursday, July 22, 2021

Reproduction Dragon's Lair Scoreboard

 I finally got around to order parts for Shaun Wood's reproduction Dragon's Lair scoreboard PCB that he sells here.



For anyone considering soldering one of these up, I found this to be a relatively easy task compared to other boards I've soldered.  Shaun provides a list of parts along with Mouser and Digikey part numbers.  Some of the parts were out of stock, so I had to find alternates.  Here are the alternates (Digikey part numbers) I ordered that seem to work fine:

  • 493-1523-ND (C1)
  • 732-2095-ND (J1)
  • S1KQCT-ND (R1, R2)


Tuesday, July 13, 2021

Finding solder bridge using thermal camera

I had a Dexter with the RESET and DIAGNOSE lines tied together somewhere.  I suspected a solder bridge but I couldn't find it.  So I decided to send some current through RESET and DIAGNOSE and get out my thermal camera to see where things were getting hot.  Here's what I saw:

I eventually found the bridge, but was not in the most intense place on the PCB:


In the future, instead of looking for the most intense spot on the PCB, I should observe the path that the heat is traveling.  The fact that the heat was traveling down and left of where I was applying power was a clue that I would find the bridge somewhere along that path.