Solenoids randomly firing.
I have replaced all of the boards and tested the as-fitted boards on the bench. The problem remains that 5 of the solenods fire randomly - the solenoids in question are not related to a specific string in the matrix. I have removed the lamps power rail as has been suggested as there may be a lamp problem interfering with the solenoid matrix - still random solenoid action.
I have rebuilt the power supply, replacing the tank capacitors and the bridges. I have replaced the mains inlet filter.
A scope on power rails and solenoid lines shows transient noise - noise not adjacent to the power supply on the source power lines. I have yet to separate the wiring loom to look for wiring shorts or cross coupling/ in the loom.
There were several small soldering and connection issues which have been addressed.
Maybe someone has had this problem before. Going through each loom, looking for a short is a last resort.
Any help appreciated. Ken
I have replaced all of the boards and tested the as-fitted boards on the bench. The problem remains that 5 of the solenods fire randomly - the solenoids in question are not related to a specific string in the matrix. I have removed the lamps power rail as has been suggested as there may be a lamp problem interfering with the solenoid matrix - still random solenoid action.
I have rebuilt the power supply, replacing the tank capacitors and the bridges. I have replaced the mains inlet filter.
A scope on power rails and solenoid lines shows transient noise - noise not adjacent to the power supply on the source power lines. I have yet to separate the wiring loom to look for wiring shorts or cross coupling/ in the loom.
There were several small soldering and connection issues which have been addressed.
Maybe someone has had this problem before. Going through each loom, looking for a short is a last resort.
Any help appreciated. Ken