This shows the change I made to the G809B to fix the design error discussed with the previous picture. I added a 220 ohm resistor in the diode string that had the lower forward voltage to allow the relay transistor to switch properly. The fix is the blue wire and surface mount resistor soldered to the diode in the middle right. This significantly improved the relay switching without having to significantly modify the card. With a scope you can see the relay still isn't cleanly switching. As the -15V switches through the turn on threshold the load of the relay switching on will pull down the -15V and cause it to turn back off. After 5-20 milliseconds of switching it then stays on properly. It seems like the later revision card is likely to have this behavior but without getting one I can't verify.
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