Akai display whine- update

[madtheory]

I understand now why tallowaters recommended cardboard. If the foil is not sitting correctly behind the LCD, it makes a very loud whining sound. This comes from the display itself. Inverter whine can also appear to come from the display, but when you lift the top panel you can hear it's from the inverter which is located next to the PSU board.

gmeredith- ya the VZ is a little more awkward. If you want to lift out the complete display board, you have to disconnect all ribbon cables and also unscrew the top PCB to disconnect the other ribbon cables. I left the top PCB in and did the replacement of the foil in situ; slightly clumsier to work with, but fine.

So then you have to remove the metal box of the display, which requires careful twisting of the 6 metal tabs, then you push it off the PCB. Next, lift off the LCD itself. The legs of the EL foil are soldered directly to tabs on the PCB, whereas the FZ is wired. So that's slightly more challenging to desolder, be careful not to burn the PCB and lift the tracks! The trick is to desolder, then let it cool for 3 mins, desolder again, etc. and apply the iron for as short a duration as you posibly can. I had to bend the the legs of the supplied foil because they're closer together than the tabs on the VZ's PCB.

Then pull the old EL foil off, it's stuck on with very sticky double sided tape. Solder the new one in re assemble and you've a nice bright blue display again.

That all reads as tricky, but it wasn't! Replacing a VCF in a Juno 106 is trickier. It took less than 30 minutes to do, from disassembly to testing to re assembly. Bear in mind that I do this kind of thing fairly often.

[nuromantix]

Where can I get this foil?
My MKS80 has started doing this, and my TX81Z is REALLY LOUD.

thanks

[madtheory]

http://www.midi-rakete.de/ for foil. But I have a suspicion that the MKS and the TX use Neon for illumination, not EL foil. Post a new thread in the help section perhaps?

[gmeredith]

Hey thanks for the great step by step VZ repacement info - that's by far the most detail I've ever gotten on it! I'll give it a go.

Nuromantix:

Are you getting a hum out of your TZ81z, or a whistle? The earlier TX81z's suffered from loud transformer hum - I have 2 of them that do it. Make sure that it's not that instead. There was some service notes issued by Yamaha a long time ago that told service agents to install a metal shield around the transformers to prevent the humming.

Cheers, Graham

[madtheory]

Hey thanks for the great step by step VZ repacement info - that's by far the most detail I've ever gotten on it! I'll give it a go.

You're welcome! Good luck with it.