OK, the last problem turned out to be a cracked trace between pins 9 and 11 of the LM3900. Apparently, the force of cutting the lead alone cracked this trace, so I'd like to ask Ken again if this might be a result of his new PCB manufacturer, since I didn't have anything remotely like this problem with other/earlier CGS PCBs.
Also, for the archive... if you can't get the VCS to cycle then setting it in cycle mode and then adjusting the trimpot can help. The effect won't take place immediately, but on the next power-up or trigger it should. My procedure was:
1. Flip the module around, with the Out connected to a VCO so I can hear when it starts cycling.
2. Adjust trimpot a little bit.
3. Power down/power up. Listen for cycling in the VCO.
4. When I got the VCS cycling, ease back on the trimpot until just the point where it stops, then bring it up again so it starts. I'm guessing this gets it as close to a 5V trigger out as possible without a scope.
Also, for the archive... if you can't get the VCS to cycle then setting it in cycle mode and then adjusting the trimpot can help. The effect won't take place immediately, but on the next power-up or trigger it should. My procedure was:
1. Flip the module around, with the Out connected to a VCO so I can hear when it starts cycling.
2. Adjust trimpot a little bit.
3. Power down/power up. Listen for cycling in the VCO.
4. When I got the VCS cycling, ease back on the trimpot until just the point where it stops, then bring it up again so it starts. I'm guessing this gets it as close to a 5V trigger out as possible without a scope.