Roland D-50 maintenance

[Pro5]

Congrats on a beautiful synth! one of my favourite digitals (hence my avatar )

If it's the same key that shows a problem, it's usually related to the electronics more than cleaning of course. This could be either the gate array chip (reads the key matrix) - had that prob on a Juno 2! - or could be something simple like a bad wire/connection on the cable. Firs thing would be to open it up and check cable is plugged in properly and that it's not got a dodgy wire or two (there will be 2 lots as it's velocity sensitive) and sounds like one for all the B keys is shorted or disconnected (or heat is making it disconnect) and the other (+ octave ground) is for note on/off. Easier to look at and test than to describe.

Tiny solder traces can cause shorts on the 'scan board' and there's a cable runs to the mainboard - check it's clear of fouling and has it's shielding in place

Really though first thing is to check it's all physically OK inside connectors and cables. Then to look into more detail at the specific wire for the keys in the matrix - easy to fix if so. Lastly it could be a damaged gate array/key reader chip - and it may be surface mounted like Juno 2 which is next to impossible to fix on your own cos such small pins for de soldering.

Try it over midi if you can see if all notes play ok - can help diagnosing - if it's ok then it's def a problem from the key reader IC back to the keybed wiring.

Oh also dismantle the keybed - clean the keys while at it to make it like new - and check the keyboard PCB (where all the contacts are) for broken tracks - one further down the line may affect all the keys on that line if intermittent maybe not though

http://home.arcor.de/richardon/richy2001/d50/sch4.gif

See a schematic there - to dyna scan board - this is what you'll want to check - the entire thing connections, shorts etc

You can download the full service manual off the net

Hopefully just a lose cable though good luck.


BTW i fixed 2 buttons that weren't working on my d-50 by carefully dismantling the tiny tact switch and cleaning it. You would typically just solder a new switch in though (cheap and easy if you can do it)

[ZenMaster]

Thanks Pro5

My friend helped me to clean it up, we checked contacts and everything seemed to look "normal". Three of the previously unresponding micro switches came to life, and the problem with the B-keys got better. Now only one is mute, three of them go straight to the max (you have to hit or press them pretty hard though) and one works like charm!!!

We didn't have enough time to dismantle the key bed, it seemed too complicated for the time issue. There were some plastic "windows" glued to the key system, are they there to hold the keys in their places? The issue could be bad contact under the key, under the grey rubber hood . . is it disassemblable? Would be weird though cause the problem is found only on the B-keys... What else could it be? Or are there more connectors inside the key bed that should be cleansed?

I haven't been able to check it via midi, but will do so next week.

[Pro5]

right ok so you need to clean the contacts then - max velocity is common problem if the contacts are not clean. the way you described it before it sounded like an electrical problem.

The B keys thing - could be coincidental - I suggest a good clean of the contacts as with any old synth should be #1 priority before troubleshooting keybed issues! All you do is remove the keys - pull of the rubber cups - clean inside the rubber cups gently (just for dust dont use any liquids) - and also dust the coppery contacts on the board where the rubbers touch - again do it dry for now - should fix it - a hell of a lot of dust builds up under there over the years. If that's doesn't work then do a better clean (google key cleaning - very common)

and yes you can pull those plastic 'windows' tabs off - they just keep the keys nice and safe when back in - glue them back in or just stick them on the old glue - they dont have to be perfect cos are not 100% 'vital'

[Herbalizer]

Hi MasterZenMaster

I´l post this link to here too if someone has similar problems with D-50
D-50 | Key Contact Repair

[ZenMaster]

Originally Posted by Pro5

right ok so you need to clean the contacts then - max velocity is common problem if the contacts are not clean. the way you described it before it sounded like an electrical problem.

The B keys thing - could be coincidental - I suggest a good clean of the contacts as with any old synth should be #1 priority before troubleshooting keybed issues! All you do is remove the keys - pull of the rubber cups - clean inside the rubber cups gently (just for dust dont use any liquids) - and also dust the coppery contacts on the board where the rubbers touch - again do it dry for now - should fix it - a hell of a lot of dust builds up under there over the years. If that's doesn't work then do a better clean (google key cleaning - very common)

and yes you can pull those plastic 'windows' tabs off - they just keep the keys nice and safe when back in - glue them back in or just stick them on the old glue - they dont have to be perfect cos are not 100% 'vital'

Originally Posted by Herbalizer

Hi MasterZenMaster

I´l post this link to here too if someone has similar problems with D-50
D-50 | Key Contact Repair

My kindest thank yous fine gentlemen
Forgot to take a midi cable to home, perhaps some day this week . . .

[FutureST]

First Post! (Hope I'm doing this correctly)

I recently purchased a Roland D-50. The "Patch Number" buttons 7 and 8 are not working. For example, I can't enter sounds; 17, 18, 27, 28,...67, 68,..87, 88. I've restored the factory settings per the manual and the Memory Card PN-D50-00 but no difference made. All other Patch Bank and Patch Number buttons are working properly. Is there something obvious I'm doing wrong? Any suggestions on how to fix this issue?

Thanks,
Bob

[Futureman84]

More than likely the 'tact' switches inside need replacing.

If you know how to solder / desolder then it's an easy job.

Otherwise you'll need a tech to do it.

Regards

[FutureST]

Thanks, was thinking something like that was going to be the case. Many years ago I was an Electronics Technician so the soldering / desoldering shouldn't be an issue (though I am a bit rusty at the craft). Do you know if the tact switches are redily available or special-order?

Best regards,
Bob

[FutureST]

Nevermind, I found them on Roland D-50 D50 keyboard repair forum..

"D-50 uses SKHHAMA010 tact switches (see attached datasheets) manufactured by ALPS (Roland p/n 13169633)."

[FutureST]

Also, after purusing the manual, I found that I can use the "Pedal Switch" to increment up on each sound in a bank (i.e., 11, 12, 13,..17, 18). However, it increments "up" only (not down) and I have to manually switch to the next bank (2, 3,...7, 8). When time permits I'll open up the unit and assess the tact switches.

Bob

Yamaha Motif ES8, Korg Extreme Pro 76, Korg Karma, Roland D-50, Roland XP-30

[Pro5]

Originally Posted by FutureST

Also, after purusing the manual, I found that I can use the "Pedal Switch" to increment up on each sound in a bank (i.e., 11, 12, 13,..17, 18). However, it increments "up" only (not down) and I have to manually switch to the next bank (2, 3,...7, 8). When time permits I'll open up the unit and assess the tact switches.

Bob

Yamaha Motif ES8, Korg Extreme Pro 76, Korg Karma, Roland D-50, Roland XP-30

How exactly would you 'increment' down?

Anyway that's how it's supposed to work. It cycles through a BANK not the whole synth's memory.

[glehner]

+
I have a D-50 and would like to know how to ground it?