ASR-10 Power Supply Issue


After being told that the 8 pin mini Din cable between an ASR-10 and an OEX-6sr was a bog standard 1-to-1 cable, I purchased one plugged it in and then had all sorts of hum which ended up with fuses F6 & F7 blowing. Replaced those and then used the Service Manual to check things in case something was wrong. Discovered when talking to The Soniq that the cable is not a 1-to-1 cable. I got the correct wiring and have since corrected my cable. However, something has happened to my power supply board. I got an ERROR 009 today when turning the ASR on and that fits with what I was seeing with connector J3 voltage tests. It now reads zero across every test on the J3 socket. J1, J2 & J4 all test within the ranges in the service manual.
Is this likely to be something on the board or is it possible that a transformer can give up like this? I presume that there are different takeoffs from the windings of the transformer so I would expect that if some of the voltage checks on some connectors are ok and on J3 is not, I suspect some other components may be at fault?

I am not well versed electrically. I know enough to be dangerous, but that is about it.
I can tell you that none of the components appear like they have overheated. None of the large capacitors appear bulged. There is no evidence of any sort of ooze or chemicals on the board at all.

Does anyone have any idea what I should be looking for?


sorry to hear the issue you described are the capacitors the original ones for the psu? if yes they are over 25 years old and they must be replaced these 8 capacitors are the same configuration as the esq-1 looking at the picture these capacitors will cast $11.58 cents i got them from mouser. so recap them yourself it will give you peace of mind it wont be needed to be replace any time soon. look up on you tube your power supply issue bradthx has a 28 minute video on the battery and the repair for the psu. good luck

I really don’t know if the capacitors are the originals. I am not sure if they have any sort of indication on them (date) that they are the originals. I am also not sure if there any tests that I would be able to do to check whether they are ok? Are you saying just to change these as the other connector voltages test ok and they would all be coming via the transformer as well which would indicate that the transformer is still ok?


Hi again,
I found an electronic repairer via a mate up the road. The keyboard is with them. I must admit to not being too confident with soldering on PCB’s. Just the worry of overheating something by being a numpty.
I emailed The Soniq asking if he may have a circuit diagram for the power supply board. I can understand why he may not share it if he does though.