Vintage Synth Repair

--- In vintagesynthrepair@yahoogroups.com, "David" <Ginahoy@a...> wrote:

> Although I haven't checked out the patch jacks yet, all the electronic
> components seem to be ok. I'm hoping all I'll have to do is calibrate
> the VCO's (something I've never done before) and clean the sliders.

The tuning procedures can be found here:

http://www.synthfool.com/openresources/
ARP2600_1973_Tuning_Procedure_(handwritten)_1of2.jpg
http://www.synthfool.com/openresources/
ARP2600_1973_Tuning_Procedure_(handwritten)_2of2.jpg

> I've been reading through the archives and found a couple of threads
> on slider maintenance. I was ROTFLMAO when I read about submerging the
> unit in a DeOxit bath (msg 657) :-))

*checks archives*  Yeah, that's funny. :-)
I've personally seen 2600 sliders that have had DeOxit sprayed in them.  Yuck.

I've cleaned 2600 sliders before, but I forgot what solvent(s) I used.  I do remember using 
LOTS of q-tips.

> Now for my question. My 3620 keyboard has always had a problem with
> erroneous (multiple) triggers. I haven't opened it to look at the
> mechanics, but many years ago a local tech told me this is a common
> problem and the fix isn't a big deal. Some keys are worse than others,
> but four or five are bad enough that spurious triggers occur during
> normal playing. 
> 
> Can anyone tell me what's involved to resolve this problem?

My guess is to check the keyboard contacts.