Vintage Synth Repair

Hi
Thanks for the response.  I eventually tore the keyboard apart over
the course of a week and finally got the keyboard subsystem out.  What
a pain!  To clean the contacts every key had to be removed.  I didn't
see the glue problem that you mentioned but knowing that now, I may
tear into everything again and see if I can cover the glue with
something like a squirt of silicon to keep it in place.

I did get the keys working again.  One or two sometimes don't respond
but overall it was a success.   Thanks for the tip on the buttons.  I
will work on them soon as there are three or four that are squirrely.

Here is a link to FlickR where I posted the repair pics.

http://www.flickr.com/photos/lonepiper/sets/72157612295420994/

 



--- In vintagesynthrepair@yahoogroups.com, "Eli Corral"
<austinkeyboards@...> wrote:
>
> Hi,
> The problem here can be that the pink glue that holds in the weights
> under the keys themselves is melting and this is a mess. It will melt
> onto the rubber contacts and circuit boards "upper and lower". If that
> is what is happening and if you can find a receipt of the original
> purchase then you can have it replace by a service center with a free
> assembly you pay labor. Good luck finding a receipt.
> To remove the melted glue I have heard of using "freeze spray" that
> the spray used to cool down circuits for troubleshooting. This will
> harden the glue and make it easy to take off the keys and board. The
> rubber contacts will need to be replace more likely. As for the panel
> switches I found that by removing the circuits boards completely and
> then cleaning off the dust then spraying a small amount of lubricant
> such as D-oxit 5 onto each TAC switch and then gently depressing and
> releasing continuously so that  the switch is cleaned out. Test the
> switch with a multi meter for continuity, making sure that when
> depress you have Zero Ohms of resistance.
> 
> Good Luck!
> Eli
> --- In vintagesynthrepair@yahoogroups.com, "LonePiper"
> <maccrimmon@> wrote:
> >
> > Hi all.
> > 
> > I was given a Roland U-20 that seems to have some keyboard problems. A
> > lot of the keys don't sound at all, or are at half volume. If you
> > knock the keyboard, or the stand even, sometime you the key will start
> > to sound. To me, it sound like there is corrosion or something on the
> > contacts. Is this something that I remedy myself? I am hoping that the
> > mechanical aspects of the Roland keyboards are close enough to others
> > that someone can answer me.
> > 
> > I took the bottom off the keyboard but that is as far as I have
> > gotten, as of yet I cannot see how to remove the actual key assembly.
> > I have a Korg DW8000 that had 2 keys malfunctioning and I was able to
> > get that working, I am hoping that this will be repairable by me also.
> > 
> > I hooked it up to another keyboard via MIDI and all worked great, so
> > pretty much the keys are muckered up.  The only other problems I have
> > found is the bank 6 button does not respond and when I try to access
> > PCM cards, it can't find them.  Have to wait to see if this is a card
> > problem or more bad contacts.
> > 
> > Thanks all
> > 
> > Thanks for your help
> >
>