Korg Mono/Poly Keys Dead

[chipaudette]

Hi All,

I've got a Korg Mono/Poly analog synth that I got off eBay for a low low price...but, of course, I got what I paid for. Many of the keys don't work, or they work intermittently.

I've got experience digging into the guts of my tube amp, but little experience digging into the guts of a synth.

Anyone got any ideas of where I should start to fix my dead keys?

Chip

[Enzo]

What model? Poly 6? POly 8? Poly800? Poly 61?

Are these the strips of gray rubber contacts with a little round volcano for each key, and under that volcano is a black conductive dot that contacts a pc board? They are in groups of maybe 6 per, and are held to the board byt a few littel rubber points that stick through holes in the board?

That is earlier ones. Later ones added a black rubber ring under there around the center one, making it a double contact.

And later still there were two rows of domes down the strip or long double domes at each key, meaning two rows of parallel contatcs on the board.

If so, those pop out if you pull gently up. Note how they go in. The oldest ones are not directional, though there is one on teh end with an extra bump... or something.

The double row ones have a deep one and a shallow one - look close - and it matters which one is towards front.

Clear them all off the board, Qtip and isopropyl, wipe down the board contacts.

I also use Qtip and isopropyl lately on the rubber contact. DOn;t use contact cleaner. I scrub each little dot with the Qtip. I don't use solvents on the rubber. I used to use pure freon, but that is a thing of the past. Other cleaners are solvents, and don;t use them.

SOme contact strips may still be available from Korg. I think most of those were Fatar keybeds, so sometimes strips from other brands that also used Fatar beds will wrok.

[chipaudette]

Hi Enzo,

Thanks for the great reply. I didn't know that you had experience with keyboards, too. Impressive.

My Korg is really a "mono/poly". That's its name. It's not a poly six or any of the others. You can check out the mono/poly at:

http://www.synthmuseum.com/korg/kormopo01.html

There's a wikipedia entry, too, but it's pretty poor.

Thanks for your suggestions regarding the key buttons. I'll take a look at them again tomorrow morning.

Chip

[Enzo]

That is from the 1980s, and I've never seen one, but 1980s seems like after gold wire contacts, and Korg mostly used rubber in those days. Nowdays Korg mostly uses Yamaha keybeds.

[thestov]

Cleaning the contacts

http://monopoly.highspies.com/keyclean.html
^
This seems to be one of the most in-depth guides on how to clean mono/poly contacts, if you haven't done so already. Really good website dedicated to the monopoly.

[Robert M. Martinelli]

Hi all,
I own a KORG DW8000, if memory serves me well it is from the early 80s, so the construction methodology should be pretty the same. I have had problems with the keyboard contacts in the past and I used some Philips 390CCS contact cleaner, as it doesn't spoil plastics and rubbers, and it did fix the problems.( BTW I think the 8000 still to be a great piece of gear IMHO ).
FWIW I think the 390CCS to be the best contact cleaner I've ever tried....It's so good I use it on my guitars' strings to keep them from prematurely oxidizing.

I've heard from a friend Philips licensed this product to another company though, and now this cleaner is sold under another name, "perfect" or something like that ( I still have a bottle or two of 390 so I guess I'll find out when I'll run out of that ).

Hope this helps

Best regards

Bob

[chipaudette]

This is a good link. I really enjoy the info!

Chip

[chipaudette]

Hi All,

After a two-year delay, I finally got back to trying to fix this keyboard. After reading about contact cleaners and getting worried about the various opinions of the effect of contact cleaner on the conductive rubber pads in keyboards, I started this thread asking about a completely different type of product for dealing with keyboard contacts...

Caig CaiKote44 for keyboard contacts

It worked pretty well. All of my keys seems to be completely functional now. Joy.

I'm just posting this update to give the thread closure for any newbie who actually uses the "Search" function.

Chip