Thanks for the feedback jatinah. It's 240VAC here, Australia.
I don't know enough about what's driving the opto yet to be able to tell exactly where its signal is coming from, but that will come in time as I work back through the circuit.
Motor checks are all good, and as mentioned earlier it drives the belt fine using an external DC supply. Cable to console looks fine too, although I haven't yet tested every pin for continuity.
On that note, I think I'll do that next - at the console board. One thing I didn't mention is that this fault happened right after the previous owner moved house. It apparently wasn't dropped or anything like that.
I was actually just getting ready to post here asking if anyone could think of a reason why moving the machine could cause this ... and now I'm wondering about that cable. It's disconnected at the top end whenever the machine is disassembled. Any other suggestions along that line of thinking are welcome.
If that turns out to be the fault, then at least I've learned more about DC motor control
I don't know enough about what's driving the opto yet to be able to tell exactly where its signal is coming from, but that will come in time as I work back through the circuit.
Motor checks are all good, and as mentioned earlier it drives the belt fine using an external DC supply. Cable to console looks fine too, although I haven't yet tested every pin for continuity.
On that note, I think I'll do that next - at the console board. One thing I didn't mention is that this fault happened right after the previous owner moved house. It apparently wasn't dropped or anything like that.
I was actually just getting ready to post here asking if anyone could think of a reason why moving the machine could cause this ... and now I'm wondering about that cable. It's disconnected at the top end whenever the machine is disassembled. Any other suggestions along that line of thinking are welcome.
If that turns out to be the fault, then at least I've learned more about DC motor control