hey,

im a touring musician and i like the sound of the chroma polaris. i
recently purchased one off ebay only to find out that there seems to
be reliabiliy issues with the buttons. i was wondering if you
thought it was a bad idea to take a polaris on tour, and if so what
other synth you would recommend. thanks.

-justin
--- In chromapolaris@yahoogroups.com, "bkuris" <benjamin.kuris@h...>
wrote:

>
> I wanted to report that I sucessfully replaced the membrane

buttons

> on one of my CPs with panel mounted push buttons. I expect that
> keyboard (which also has this replaced DAC and new s/h caps) to

run

> until the EPROMS fail.
>
> The whole proceedure took at least 14hrs and should be done only

as a

> least resort for cases of damaged flex wires, or when you discover
> that the actual switch membrane has worn out. Sooner or later the
> control panels will fail on most CPs-- here is how you fix them:
>
> 1) Remove control panel PCBs (Chroma Polaris must be open see

service

> manual). Cut off or tape down the flex ribbon.
>
> 2) Drill holes for every button. I recommend using the upper

right

> corner to preserve as much text as possible. I drilled from the
> outside in, several of the labels (eg. "A") ripped free, but I

glued

> them back down. Use a large bit to clean the hole on the backside

to

> provide a flush or bevelled edge for the switches.
>
> 2) Switches. You will need around 60 and the best deal I found

was

> at www.all-electronics.com for surplus sub-miniature SPDTs.

Solder

> leads will be very helpful (there are about 140 wires that need to

be

> soldered so anything helps!). I bend the leads prior to mounting

so

> have as much clearance as possible.
>
> 3a) There was still a clearance problem with many buttons hitting

a

> half dozen or so ICs on the control panel. I solved this by

removing

> the offending ICs, desoldering the sockets (requires decent

soldering

> skills), and then soldering them back down. I was able to just

bend

> the PCB to make up the remaining difference.
>
> 3b) (optional) desolder old flex connectors
>
> 4) Put the PCBs away for a while. Print out the last few pages of
> the service manual with the button wiring chart. I color

highlighted

> to save time. wwww.rhodeschroma.com is hosting the service manual.
>
> 5) I used 2 different colors of thin solid-core wire (eg. wire

wrap

> wire). One for strobes, one for switch signals. Wire them all

up,

> it will take a very long time, be careful with how you run the

wires,

> try to bend into right angles and run them against the panel to

keep

> things neat.
> 6) Don't forget to add a wires that will eventually get solder to

the

> PCBs and ∗label them∗. If you look at where they will be going,

the

> switches you should use as the source of these wires will be
> obvious. Remember that STB0-STB2 go to a different place then the

SW

> lines.
>
> 7) install PCBS and solder the STB and SW lines. Test it all out--

> good luck. I'm a skilled tech and I had 1 bad solder joint out of
> the nearly 200 solder joints but its easy to use a multimeter to
> troubleshoot as long as you don't scramble up the connection

diagram

> (in which case the LEDs will provide some clue).
>
> I will post a picture eventually...
> Due to the time this proceedure takes, I don't think it is

feasible

> to pay someone to do it for you as it would cost at least $400

which

> is close to the price of a used Polaris. I would charge $500

(more

> if it needs to be done in less then a month). Another option is

to

> have PCBs manufactured, but that also means machining a new panel

so

> that switches line up. Given the size of the panel and expected
> volume, it would probably also end up in the $500 range. A final
> option is to use MIDI which has performance disadvantages.
>
> -Ben