Hello to fellow synth enthusiasts,
I have a question about a Roland D-20 synth. I bought it from a dealer up north almost four years ago (I’m in Texas) and have really enjoyed it, although I’ve probably put less than 24 hours worth of playing on it in that time. It’s been working great until just yesterday when it started acting weird. I powered it off and powered it on to reset it, and when it powered on, the top row of characters in the display were all solid rectangles and the synth didn’t make any sound or otherwise respond. I powered it off and on again and got the same result. To say I was frustrated is an understatement.
The story does have a happy ending. I looked online and found a couple of postings stating that the synth needed to be opened up and either the battery removed and changed and/or the voice ROMs removed and replaced. I gingerly opened the synth up, popped out one of the ROMs, carefully put it back in place, slid the battery out of its holder (I wish all my synths had a battery holder like this), replaced it, replaced the bottom cover, powered the synth on and it’s been working find since then (all of 3 hours, but I’m cautiously optimistic).
My question is - what’s going on with the synth? What causes it to freeze up, and how did my surgical procedure appear to fix it? The ROMs were well seated, but something about them looked like they might have been removed before, possibly for the same issue. Any information that can be shared by the collective wisdom would be greatly appreciated.
Thanks in advance.
After a while the contacts between the chips and the sockets gain a thin layer of oxidation and lose a little bit of conductivity. I recently repaired a Roland d10 where the processor needed to be pulled out and the contacts cleaned with isoalcohol. All worked well again.
Regard Darren.
Hi bmcginney and Darren,
My D20 has been in storage for years. I pulled it out today because my partner wanted to start learning piano. But my D20 has the exact same problem as yours. Top row of display characters are solid rectangles with nothing on the bottom and no other LEDs or bootup-like happenings.
I immediately went out and purchased the most common flat battery for computers and things like this (2032 - yup, good guess, cause internal battery is 2032). After changing, still no improvements.
Question is…where on the circuit board are the voice roms located that you pulled out and reseated? Darren, you mentioned they might need to be removed and cleaned with isoalcohol. But which ones are they? Any possibility of either pics or a discription?
I would appreciate any help you might be able to provide.
Thanks so much.
Darren (yup, I’m Darren too!)
Hi, Darren,
Thanks for your question. If you’ve already opened your D-20 up, you know that the main board(s) are actually on the bottom (if memory serves). I don’t have any pictures to share, but I do remember that the two rom ICs that I took out were in sockets, they were right together, and that they were labelled with some sort of code that included an “A” marking on one of them and a “B” marking on the other. Since they were in sockets, I figured I had nothing to lose in taking them out and putting them back in.
I did a quick cursory internet search and found a site with service notes for the D-20 that look to have better information. I didn’t have this when I did the work on mine; this would have been helpful. Anyway, the URL D 20 Roland SERVICE MANUAL | SynthXL - Service & Repair Manual includes links for the Service Notes and both Owners Manuals. The Service Notes includes disassembly instructions and, after further exploration, a nice drawing of the board indicating the locations of ICs 13 and 14, which I believe is what you want.
All I did was gently pry them out and reseat them; I might have cleaned the pins, but quickly and in passing. Once I put the synth back together and powered it on, it worked great.
Good luck.
Thanks so much for getting back to me. I really appreciate it.
So, we opened up the D20 again and were only able to find 1 IC chip that was removable. IC 13 & 14 are soldered chips on my board. We did remove the Intel chip and cleaned its contacts (both on the chip and the PCB) but no luck. Still not working.
See MB pics and chip pics attached.
I am guessing the problem is bigger than a simple cleaning or battery replacement. Any idea if this is worth repairing? I don’t mind throwing a few hundred at it for time/labour and parts if it can be repaired. I am in western Canada if you have any ideas of whom I could go to for further assistance.
Thanks again.
Darren
Hi again, Darren,
Thanks for your reply and expecially the pic. OK, so when looking at your pic as sent, I’m about 99% certain that the chips I pried out and put back were the two larger oblong chips that are horizontal in the view that you have sent. After looking back at the D-20 Service Notes, I see that these are not ICs 13 and 14 (sorry, I should have been more thorough), but ICs 26 and 27, evident on p. 18 of the Service Notes, which includes a drawing of the board in your picture, and a block diagram on p. 8 of the Service Notes, which identifies IC 26 and 27 as “PCM ROM.” I’m sorry for my earlier mislabeling. Anyway, these two ICs should be in sockets, making their removal and replacement pretty easy. I say try these two. If you do, please report back whether it works.
Do get the service notes if you can; my reply has shown their usefulness.
Hope this helps and, again, good luck.
