Disklavier Repair

[Eriknbkk]

I have a Disklavier board that needs a new power supply, seems the part is difficult to find. Is there anyone here that has experience fixing Disklavier boards, that may want to take on the work?

Much thanks - Erik

[g1]

It may help to tell us where you are located. Shipping and line voltage may be considerations.

[Jazz P Bass]

And what is the mysterious 'part' that is hard to locate?
What is the exact model number?

[Eriknbkk]

I am in Thailand, the power supply is the part they can not get here. Model is DGB1CD year 2006
120V 60 Hz 180W.
I am just going off what the Yamaha tech told me that the piece needing replaced on the board
is the power supply as pointed to in picture.
But you can also see this on the back of the board. Where this part sits.
Thanks for taking a look.

[Mick Bailey]

The entire board assembly appears to be the power supply - the damaged area is just one part of it.

It's possible for an experienced repair person to fix the power supply without the need to replace the complete board. The damaged track can be repaired and the problem that caused this damage put right. The affected components are most likely to be standard electronics supply parts which should be available in Thailand.

This type of power supply is now universal in consumer equipment, so any good all-round electronics repair shop that handles repairs at component level should be able to help. Ask if they're able to do SMPS (switch mode power supply) repairs. Also many general industrial electronics repair shops can handle this type of work.

[Eriknbkk]

Mick, Thank you very much for the reply I will begin my search locally if not I have been directed to TAP out of So. Cal. but I will see what I can find here first.

Thanks again, Erik

[Mick Bailey]

There's a specialist repair place in the UK but shipping costs may be prohibitive - https://www.puretechsolutions.co.uk/disklavier-repairs/

They say "We also have a test bed for the Power Supply (SMPS) on the MarkII and MarkIII disklavier and the Grantouch pianos. We are able to test/diagnose these and repair to component level with a good stock of parts."

It could be worthwhile emailing them with the pictures to get an opinion and maybe some options.

[dmeek]

This is the schematic for the MX1Z power supply. Looks to be the same as the DGB1CD. I would guess that IC1 "YH-S1" is burnt out. Probably a Yamaha custom part.

[Mick Bailey]

I was thinking that there would be regular discrete components hidden by the heatsink, but looking at the schematic and again at the pictures It looks like you're right - YH-S1 is probably an encapsulated module containing the switching components. The schematic looks like it may differ to the board in that the positive rectified supply C13 looks like it connects to different pins on IC1.

I took a look at the price for a replacement power supply. Gulp! https://reverb.com/uk/item/3100463-y...bly-for-dgb1cd

[dmeek]

Here's the PCB layout for the MX1Z

MX1Z PWB layout.pdf

[Mick Bailey]

I looked around for IC1 but can find no reference anywhere, other than in the service manual. Maybe the specialist repairers or Yamaha authorized repair centres have (or had) these ICs. I have though sometimes encountered ICs in other equipment that were never sold as spare parts - they were fitted only to PCBs only at manufacture.

[dmeek]

Here is the parts list. Looks like IC1 is referred to by 1c - HIC Unit (VN81310). Impossible to find I'm sure.

mx1z-PL.pdf