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Polaris Membranes installed, Bank / program select not totally working right

Polaris Membranes installed, Bank / program select not totally working right

2014-06-19 by wonderbromusic@...

Hi all,


I've recently purchased and installed new membranes on my Polaris II, and for the most part, they're working great, the keyboard makes sound like all good synths should etc.


There is one issue, so I thought I'd ask the real experts - in my Bank / Program select, I can choose any bank, but I can't get to programs 1 through 6 (accessing 7 through 12 work great!).  All other membrane buttons work perfectly.


When I click a bank, then select any of the programs between 1 - 4, it actually switches to F7. Selecting H1 for example will actually call up G7 all the way through to bank K.  If I select program 5 or 6 at any time from any bank, it actually crashes the keyboard. Again, banks A - K using Programs 7 - 12 call up the presets correctly.


All the LEDs work great - for example I click a bank and programs 1 - 12 all light up waiting to be pushed, but at the moment, I'm stuck with only being able to access half the presets, the big drag being that 'store / erase program' are also assigned as an 'upper function' on Program 1 and 2 respectively as well.  Left membrane, no issues.


Checked the ribbon connections, they look clean without any bits from the last membrane floating in there from what I can see (and I removed a few changing them!).  I was super fussy about making sure they lined up with the pins as best as possible. All ribbons are set well in the connections. 


I'm thinking there may be either a short, or something going on with the ribbon config that I've missed, but I'm definitely no expert. 


I took a really small risk and bought this board for a great price, even with the membranes getting replaced.  At purchase it wasn't functional, with a hope a membrane fix would resolve it, so if it's something else, well... I guess I bought it...


I'm half way there! I consider just getting it to make sound a total win. However as I'm sure anyone who's played this bit of hardware would agree it would be great to get this fully functioning - I would appreciate any insight as to what could possibly be the issue or how to better troubleshoot this. 


I'll admit, even with half the patches available at the moment, I'm already totally in love with this synth. I've gone through the conversations here and I don't see similar issues, so if there's one posted similar to this that I've missed I'd appreciate being directed to it, or if anyone has any ideas as to what may be going on, that would be very helpful as well.


Thanks in advance,


Adam

RE: [chromapolaris] Polaris Membranes installed, Bank / program select not totally working right

2014-06-19 by Paul D. DeRocco

> From: Adam
>
> There is one issue, so I thought I'd ask the real experts -
> in my Bank / Program select, I can choose any bank, but I
> can't get to programs 1 through 6 (accessing 7 through 12
> work great!). All other membrane buttons work perfectly.
>
> When I click a bank, then select any of the programs between
> 1 - 4, it actually switches to F7. Selecting H1 for example
> will actually call up G7 all the way through to bank K. If I
> select program 5 or 6 at any time from any bank, it actually
> crashes the keyboard. Again, banks A - K using Programs 7 -
> 12 call up the presets correctly.
>
> Checked the ribbon connections, they look clean without any
> bits from the last membrane floating in there from what I can
> see (and I removed a few changing them!). I was super fussy
> about making sure they lined up with the pins as best as
> possible. All ribbons are set well in the connections.

I'm surprised you didn't contact me, since I'm the guy who sold the panels
to you.

Since the panels were tested by the manufacturer, and then tested again by
me before they went out, the problem is almost certainly not the panels.
Possibilities are:

1) There's still a bit of the old tail left inside the connector shorting
something out, or perhaps just some ink flakes. On one of my Polarises, I
had one connector that was so impervious to cleaning that I eventually had
to remove it and put in a new one. It took an eye loupe and a bright
flashlight to see that there was still some crud in there behind the
contacts.

2) A failing Z1 or Z3 on the right panel board.

3) A cold solder joint on the connector, Z1 or Z3.

The crashing is mysterious to me. I can't imagine how any electrical
problem in the switch matrix could crash the CPU. Perhaps there is
unrelated corruption in the CMOS memory. Once the switch issue is fixed,
if the crash problem is still there, saving sounds via MIDI, clearing the
memory, and reloading the sounds might clear it up. If it does clear it
up, then I've got some head scratching to do.

--

Ciao, Paul D. DeRocco
Paul mailto:pderocco@...