No A or D# on Yamaha DGX 205

[DGX20521]

Hi all - both A and D# were fine one day and the next day stopped making any sound in any octave on my Yamaha DGX-205. Based on advice elsewhere I’ve opened it up and cleaned the rubber pads along the keys and the contacts with alcohol wipes and q tips. Any tips? Are these getting grouped together by octave somewhere else in the system that may have come undone? Thank you for any suggestions!

Edited to add - I also tried to take a peek at the maintenance manual that shows up on elektrotanya but it’s a bit beyond me https://elektrotanya.com/cgi-bin/do...fj5629o&fid=224603&file=yamaha_dgx-205_sm.pdf

 

[DGX20521]

Holy moly, folks! Gave it one more pass wiping the contacts on the circuit for those keys…and it is fixed! Thanks to all in this forum - tips here are a big part of how I figured it out.

 

[SeaGtGruff]

I'm glad you were able to get it resolved!

 

[DGX20521]

Thanks!

 

[delaware dave]

Glad I could help.

Did I actually respond to this thread?

 

[DGX20521]

Unfortunately, it has happened again! Same keys not making sounds. I’m going to open up and clean again but I’m wondering if something else might be going on since it’s the same keys having problems at a different time - any thoughts for a fix?

 

[DGX20521]

Coming back to this thread to say for posterity - I continue to have this problem intermittently / uncontrollably (A and D# making no sound in all octaves).

Examples: The first time, opening everything up and cleaning the contacts ultimately worked. Another time, I turned the keyboard off, turned it upside down, then turned it on again and the sound came back. (Unfortunately this "trick" hasn't worked since.) Another time, I ignored the problem for a while and then the sound came back on a random day.

I suspect it's a worn contact of some sort as opposed to dust - something that gets knocked in and out of place. Worried it might be beyond me to fix.

 

[happyrat1]

In all octaves? Look at the connecting diodes in the matrix for cracked or cold solder joints or blown polarity. Look for faulty ribbon connections in the switching matrix as well.

 

[happyrat1]

Do some continuity tests with an ohmmeter.

 

[DGX20521]

Thanks for the tips happyrat1!

 

[amwilburn]

Not just the wiring; You might not want to hear this, but I've had problems repairing a PSR (think it was an s970) with the same keys in all octaves being affected, turned out one of the keyboard relay pcb's was gone. Luckily still under warranty, and the head warranty guy happened to be in town so we went over it together). You'll need the service manual to figure out which one is gone (there's only an upper and a lower on a 61 key, but the DGX205 being 76 keys, it might have 3 key relay pcbs).

Mark