Esoniq SQ80 – [Garbled Display]
Hi all, was hoping someone could help me out. I’ve this old Esoniq SQ80 that a friend gave to me years ago, but I’ve never really had the chance to use it. I set it up the other day and gave it a play with. Sounded great, and all functions were working perfectly until about 10 mins in… the screen scrambled into strange/broken error shapes/symbols. I could still play notes though. I powered off for a bit and turned it back on, but the scrambled display was still there, and this time no sound. I assume it was mainly due to the fact I couldn’t navigate off the startup screen. Anyway, beforehand it had also said low voltage, which I am aware is to do with the battery for the RAM. I was wondering if anyone had any bets on what’s wrong with it and how much that might cost to fix (UK). The initial research suggested a new battery for the RAM (which I’m going to do anyway), but there is also a chance it could be something a bit more complex than that. Any help would be great! It would be awesome to try and diagnose exactly where the fault is before I start taking it to engineers etc.
Cheers:)
It’s hard to say for sure, sometimes these just need internal cables disconnected and the headers cleaned. Other times they need quite a bit of work.
Usually the display panel when partially working will boot into a self-test mode where different buttons on the front panel print various characters on the display. The fact that yours isn’t entering self test mode narrows it down somewhat. I’d try disconnecting the front panel board from the main board and see if it boots in self test mode or if the display still looks like that or not. There are then two cases.
Case 1: When disconnected from the main board the display still doesn’t enter self-test mode. In this case you’re probably dealing with a power supply issue or the issue is localized to the display board. Best course of action from there is to check the power supply as described in the SQ80 Service Manual page 13-14. If the power supply all seems healthy then the issue must be on the front panel board. Could be a bad capacitor, reset line or the microcontroller to name a few possibilities.
Case 2: When disconnected from the main board the panel board does enter self test mode. This can also be a power supply issue so refer to the power supply testing in the service manual. If the power supply is good then it’s a mainboard fault which can be pretty tough to fix.
If you take it to a tech I highly recommend you find one that has worked on Ensoniqs before. Especially if it’s a mainboard fault.
2 Likes
