Roland D-50 D50 keyboard repair forum..

[Mars Amp Repair]

Um...don't be surprised if the unit goes back to doing the playing only when the keys are released thing.

We had 2 of the D-50's at different times doing the same thing & both of them came back after a week when we re-flowed flat pack gate array IC-1 & the RAM chip IC-2 on the DynaScan board. You can't find that Gate array anywhere and it's not the problem anyway.

It turned out that the heat must have temporarily cured the issue, but then came right back. We ended up replacing the RAM on that board & that resolved the issue permanently on both keyboards. The original number for IC2 is LC3517...we found a sub #6116SA15TPG from Avnet Electronics Marketing - Electronic Components Distributor Services, Datasheet PDF Download, Part Number Search 4.5 Million + Components - Avnet Express for $1.83. Just plug that part number in on their search machine.

Hopefully yours will continue to operate, but here's the ultimate solution if it doesn't...glen

[jkamen]

Um...don't be surprised if the unit goes back to doing the playing only when the keys are released thing.

We had 2 of the D-50's at different times doing the same thing & both of them came back after a week when we re-flowed flat pack gate array IC-1 & the RAM chip IC-2 on the DynaScan board. You can't find that Gate array anywhere and it's not the problem anyway.

It turned out that the heat must have temporarily cured the issue, but then came right back. We ended up replacing the RAM on that board & that resolved the issue permanently on both keyboards. The original number for IC2 is LC3517...we found a sub #6116SA15TPG from Avnet Electronics Marketing - Electronic Components Distributor Services, Datasheet PDF Download, Part Number Search 4.5 Million + Components - Avnet Express for $1.83. Just plug that part number in on their search machine.

Hopefully yours will continue to operate, but here's the ultimate solution if it doesn't...glen

First - thanks to all for sharing their experiences with this issue with the D-50. I just got one of these beauties the other night. I got it home, plugged in my headphones and played with it for hours. The very next day when I turned it on, it exhibited the behavior described in this thread.

I'm pretty handy with a soldering iron so I tried "touching up" all the solder on IC2 (I did not try IC1, at least not yet). My D-50 is still exhibiting the issue.

So my question is simple - I want to replace the IC2, the 6116, but when I go to Avnet they won't sell me any less than 300 at a time. Seeing as how I don't have 300 D-50's, is there a place I can buy a single 6116?

Thanks in advance,
Jeff

[52 Bill]

So my question is simple - I want to replace the IC2, the 6116, but when I go to Avnet they won't sell me any less than 300 at a time. Seeing as how I don't have 300 D-50's, is there a place I can buy a single 6116?

Thanks in advance,
Jeff

Try eBay. Search both numbers.

[Enzo]

Jameco has them, cheap

Jameco Electronics - Electronic Components Distributor

[Enzo]

Jameco has them, cheap

Jameco Electronics - Electronic Components Distributor

[jkamen]

Jameco has them, cheap

Jameco Electronics - Electronic Components Distributor

Thanks Enzo! I just ordered Jameco part no. 42796. I hope that's the right one! There doesn't seem to be an exact replacement for the HM6116ASP-12.

[Mars Amp Repair]

Thanx Enzo,
Thinking back we ran into the same problem...we probably got them from Jameco, too.

BTW, I've used that silly turntable stand you sold me about 3 times in the past month.

Thanx, again...glen

[jkamen]

Well, I got my 6116 from Jameco today. 2 days coast to coast is not bad at all via USPS!

However, it's the wrong one. It's twice as wide as the original, so it won't fit on the Dyna Scan circuit board. Now I am at a loss as I can't tell by the 6116 part numbers which is the correct one. Jameco's closed on the weekends, but perhaps I'll call them on Monday.

[Enzo]

Darn, well we tried.

There are a lot of equivalent memory ICs, all the 6116 choices on that priginal page showed 24 pin DIP. And they are 2Kx8 SRAM.

Are yours 24 pin barrow DIP or are they only 20 pin or 22 pin?

Something like this may wind up working
4116-15: MAJOR BRANDS: ICs & Semiconductors

But give their applications people a chance to help

Call them monday, and have ALL the alphabet soup from your old chips at hand.

[jkamen]

You guys are gonna love this story...

So in a moment of desperation, I went scavenging in my stockpiles of old computer junk (dating waaaay back). I was about to give up when I spotted an old Dove FaxModem for a Mac SE circa 1990. What was sitting on the faxmodem board with a glowing aura around it with a heavenly "aaahhhhh" singing in the background (possible synthesized from a D-50)? A 24-pin 6116!! I carefuly de-soldered it from the modem (took me over an hour, the thing was stubborn) and quickly popped it in the dyna scan board. Popped the board back in the D-50 and success! At least so far. Now I know for sure what the issue was (but I didn't doubt it really based on this thread), and if I have to I can find the right part, or even fabricate an adapter for the "wider" 6116 I got from Jameco.

Guys, thanks so much for all the help! Happy playing!!

Jeff

[doctor]

You guys are gonna love this story...

So in a moment of desperation, I went scavenging in my stockpiles of old computer junk (dating waaaay back). I was about to give up when I spotted an old Dove FaxModem for a Mac SE circa 1990. What was sitting on the faxmodem board with a glowing aura around it with a heavenly "aaahhhhh" singing in the background (possible synthesized from a D-50)? A 24-pin 6116!! I carefuly de-soldered it from the modem (took me over an hour, the thing was stubborn) and quickly popped it in the dyna scan board. Popped the board back in the D-50 and success! At least so far. Now I know for sure what the issue was (but I didn't doubt it really based on this thread), and if I have to I can find the right part, or even fabricate an adapter for the "wider" 6116 I got from Jameco.

Guys, thanks so much for all the help! Happy playing!!

Jeff

To anyone who will have to look for such chip.

Original chip used in this board is LC3517AS having so called “Skinny DIP” package.
It is ordinary 2Kx8 SRAM with access time 120ns.

The direct replacements are for example: LH5116D, SRM2016N, SRM2017N, and SRM2018N.

It is possible also to use any 2Kx8 SRAM (having 100-120 ns access time) either with suitable print adapter or, in worst case, to glue wide chip on the back and solder pins by wires.
Sure, it is not most elegant solution, but sometimes there is no choice.

[Mars Amp Repair]

Hey NP,
it's little gems like this that keep everyone from having to struggle by repeating what others have already struggled through & succeeded . That's why I love this forum...glen

[Riva Stereokromatik]

Roland D-50 display are 'crazy '...

Hello everybody ... I have a strange problem in my D-50, or when I turn on when I start changing patches, the characters on the display are crazy, full of ' $ $ $ $ $ $ $ ' ... someone has been there and managed to fix it?

[peterr88]

hello mate, I have the same problem with my roland d50

[bkahuna]

It looks to me like your memory backup battery died. I would try replacing it and reloading the factory patches...actually, reverse that. Try reloading the factory patches first. If that solves your issue until you turn the unit off, then you'll know the battery is at fault.