Good day - I picked up an ESQ-1 that has a line of non-functioning soft buttons. The line travels to “Row 6” input (pin 10) of the display board. The buttons are internal bank 2, soft button 2, 5, edit, filter, and OS2.
I am receiving continuity between each solder point
I re-seated all plugs and cleaned pin connectors with deoxit
I re-heated all solder joints on the button PCB and the pin connectors on the display PCB (I have the earlier version with two boards)
I blew out internal dust and debris with a light air compressor
I replaced the internal battery (and hard reset)
I upgraded EPROM to OS 3.5
I cannot hard reset without access to several buttons mentioned above. I am at a loss for additional troubleshooting options and am ready to sell if I cannot find a local service option (Pittsburgh PA). Looking forward to any synth wisdom that can be shared as I’m new to the synth world.
I suppose you already have in your hands the service manual and schematics.
To do an hard reset just remove/disconnect internal battery a few minutes with switch on and mains disconnected.
After fixing knowns issues listed in the service manual, you should be able, with the help of schematics, to locate the problem. Check for shorts in the keyboard matrix.
Hope this helps.
I do have that resource and even corresponded with Rainer Buchty. I was able to trace the path to row 6 (10th pin) of the controller PCB to display PCB and have full continuity all the way. I’m not skilled enough to read the schematic beyond that. At this point, I’ve exhausted all of the options that are available in forums and web and am going to list on Reverb. The synth is fully functioning minus those buttons—which loses accesses to 6+ internal voices, adjusting and oscillator and filter and editing a sequence .
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