by DRebber »
Sun Feb 27, 2011 5:37 pm
Dale,
You are correct. Logic Common can be found at the Central Control Computer on P2 Pins 2, 27, & 29. It will terminate on the Mech Control PCB at J1 Pin 11.
Power Common on the Central Control Computer is at P2 Pins 8, 10, 21, & 22. That ground terminates on the Mech Ctrl PCB at J1 Pin 10.
The reason for the confusion is that the CCC schematic shows the broken downward arrowhead symbol for ground as being the Logic Common at the P2 Connector. Without looking at the rest of the Mech Control PCB schematic, I just looked at the incoming signals at J1 and I guess whoever drew the new solid state Mech Ctrl PCB schema switched the signal designation to the downward "pitchfork" type.
I really do apologize for the confusion. I guess I need to slow down and take a breather every once in a while. However, in my defense, I always believed the pitchfork to be chassis ground for power. Conversely, the broken arrowhead was used most commonly for logic ground. Nonetheless, I'll own this mistake. If you need anything, contact me @ david "dot" rebber "at" att "dot" net, I will do whatever is necessary to help you out.
You are also correct that most of the schematics given with nostalgia models are somewhat vague. I have seen the service info packages included with these units. I would assume that AA or Rock-Ola felt it would be best if a home user did not attempt repairs. At any rate, hopefully we will get you back up and running.
Respectfully,
David