Hello, I know it’s an old post but I hope I can get a reply.
Can you tell me which capacitor is that? The 3.3mf 50V ?
That was some time ago. I wish i kept a photo or a note. i really don’t recall it but it was next to the 555. Try to google 555 monostable circuit and they will help identifying to which pins the capacitor in question is connected.
If you can post a close up photo to that area on the board, it might be helpful.
Hi, I’m attaching a photo showing the area where the 555 is.
Maybe you mean C28?
I also discovered that the capacitor C26 to the left of the pot is missing.
I could find out that it’s 220mf probably 16V and I soldered it.
The area under it wasn’t clean. It seems that the original capacitor fell off and left this liquid that also smells bad.
I wish I could have clear photos of the same “working” PCB since I can’t find any schematic online.
The link below has some schematics but not sure they are accurate. The cap in question should be connected to pins 2 and 6 because that is what triggers the 555 to change output.
http://www.tauntek.com/ASR10.htm
I think it is c28. Mine also was leaking changed it and it was all good. Use a multimeter to see which cap is connected to 2 and 6 and which one to the voltage supply rail so you can figure out the right one.
All I did was clean the keybed with 91% Isopropyl and I never had an issue with the synth calibrating since! Sorry for the late reply!
Thank you for your help. It IS C28 and I replaced C26 too as well as the ribbon cable between the 2 PCBs, it had 3 cut wires.
I still had the calibration error till I replaced the 74HS238 (U8) that’s beside the capacitor C28.
The electrolyte from C28 went under the IC and damaged it.
Now everything is fine.
Thank you very much.
GREAT, these caps are really annoying. Ive repaired a Roland xp50 about 3 weeks ago. It was plagued with almost 20 leaking smd caps. Corroded at least 4 pcb lines.
Hello Keyboardist, I have 2 XP50’s with the same problem, can you fix one out of the 2?, If you are in Texas even better…
I had one being repaired but the tech. closed the shop and I got it back.
The other one has no output either.
Not many people were successful fixing this caps.
Let me know…Thanx
Hi,
Sure, but I’m in California / Los Angeles. Please bare in mind the issue might be due to a different cause hence it it needs to be diagnosed first.