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A few pesky issues...and Frankensteining a Polysix

A few pesky issues...and Frankensteining a Polysix

2008-03-12 by mydadvsyours

Hey there. I'm in the process of fixing one of my polysixes. I'm pretty close to complete. I 
have a few remaining issues and was just wondering if any of you could tell me exactly 
where/what on the KLM-367 board I'd need to fix in order to get these issues resolved. (I 
know that most of the problems revolve around the 7408's at IC31 and IC32...). As 
mentioned, I have another polysix that i'm using for parts and have pretty much swapped 
all of the boards...and the problems mentioned above are still present.

Here are my problems:

- Chorus always on (no difference between either of the 3 effects, but speed/emphasis 
adjustment still works)
- Bank D and Program 4 or 5(?) lights stay on all the time
- VCO selector only outputs Sawtooth and PWM waveforms
- Attenuator doesn't do anything (but the EG selector seems to work ok...now!)
- Mod wheel has no effect
- The memory section is a little wonky

So yeah, any help or suggestions would be greatly appreciated...

Arturo.....

ps. Also, i'd like to not have that second polysix goto waste. does anyone know if its 
possible to use the circuit boards for other applications (ie. external filter, wave generator,  
etc). If you know of any sites that show how to frankenstein polysix modules, lemme 
know!

Re: A few pesky issues...and Frankensteining a Polysix

2008-03-13 by gil_we

There' a lot of info about these type of problems on the archives,
just search ;)

Basically what you have is an acid eaten board (KLM367),
you need to retrace and replace the ICs around the battery area.

I must say that although I already fixed a few, the last one was a
pain and I ended up returning it to the owner. I fixed most problems
except for the memory selector which was acting strangely, again check
the archives.

--- In PolySix@yahoogroups.com, "mydadvsyours" <arturo00@...> wrote:
>
> Hey there. I'm in the process of fixing one of my polysixes. I'm
pretty close to complete. I 
> have a few remaining issues and was just wondering if any of you
could tell me exactly 
> where/what on the KLM-367 board I'd need to fix in order to get
these issues resolved. (I 
> know that most of the problems revolve around the 7408's at IC31 and
IC32...). As 
> mentioned, I have another polysix that i'm using for parts and have
pretty much swapped 
> all of the boards...and the problems mentioned above are still present.
> 
> Here are my problems:
> 
> - Chorus always on (no difference between either of the 3 effects,
but speed/emphasis 
> adjustment still works)
> - Bank D and Program 4 or 5(?) lights stay on all the time
> - VCO selector only outputs Sawtooth and PWM waveforms
> - Attenuator doesn't do anything (but the EG selector seems to work
ok...now!)
> - Mod wheel has no effect
> - The memory section is a little wonky
> 
> So yeah, any help or suggestions would be greatly appreciated...
> 
> Arturo.....
> 
> ps. Also, i'd like to not have that second polysix goto waste. does
anyone know if its 
> possible to use the circuit boards for other applications (ie.
external filter, wave generator,  
> etc). If you know of any sites that show how to frankenstein polysix
modules, lemme 
> know!
>

Re: A few pesky issues...and Frankensteining a Polysix

2008-03-13 by mydadvsyours

Thanks for the reply!

Oh yeah, I'm fully aware of the battery issue and I've done plenty of
retracing around IC31 and have fixed many of the major problems. I was
just hoping to get some specific info to help accelerate the process.
But, I have the schematics now so that'll help quite a bit. And I'll
take your advice and do some searching. I already had a good read
through of some of the more recent posts and found some invaluable
info in there.

Is it necessary to replace the IC's if the traces are being taken care
of? it *looks* like it's in good shape, but I guess looks can be
deceiving.

I will also note that the Effects section seems to be working just
fine now.


--- In PolySix@yahoogroups.com, "gil_we" <gil_we@...> wrote:
>
> There' a lot of info about these type of problems on the archives,
> just search ;)
> 
> Basically what you have is an acid eaten board (KLM367),
> you need to retrace and replace the ICs around the battery area.
> 
> I must say that although I already fixed a few, the last one was a
> pain and I ended up returning it to the owner. I fixed most problems
> except for the memory selector which was acting strangely, again check
> the archives.
> 
> --- In PolySix@yahoogroups.com, "mydadvsyours" <arturo00@> wrote:
> >
> > Hey there. I'm in the process of fixing one of my polysixes. I'm
> pretty close to complete. I 
> > have a few remaining issues and was just wondering if any of you
> could tell me exactly 
> > where/what on the KLM-367 board I'd need to fix in order to get
> these issues resolved. (I 
> > know that most of the problems revolve around the 7408's at IC31 and
> IC32...). As 
> > mentioned, I have another polysix that i'm using for parts and have
> pretty much swapped 
> > all of the boards...and the problems mentioned above are still
present.
Show quoted textHide quoted text
> > 
> > Here are my problems:
> > 
> > - Chorus always on (no difference between either of the 3 effects,
> but speed/emphasis 
> > adjustment still works)
> > - Bank D and Program 4 or 5(?) lights stay on all the time
> > - VCO selector only outputs Sawtooth and PWM waveforms
> > - Attenuator doesn't do anything (but the EG selector seems to work
> ok...now!)
> > - Mod wheel has no effect
> > - The memory section is a little wonky
> > 
> > So yeah, any help or suggestions would be greatly appreciated...
> > 
> > Arturo.....
> > 
> > ps. Also, i'd like to not have that second polysix goto waste. does
> anyone know if its 
> > possible to use the circuit boards for other applications (ie.
> external filter, wave generator,  
> > etc). If you know of any sites that show how to frankenstein polysix
> modules, lemme 
> > know!
> >
>

Re: A few pesky issues...and Frankensteining a Polysix

2008-03-15 by gil_we

You must replace each IC a the area. The acid gets inside them.


--- In PolySix@yahoogroups.com, "mydadvsyours" <arturo00@...> wrote:
>
> Thanks for the reply!
> 
> Oh yeah, I'm fully aware of the battery issue and I've done plenty 
of
> retracing around IC31 and have fixed many of the major problems. I 
was
> just hoping to get some specific info to help accelerate the 
process.
> But, I have the schematics now so that'll help quite a bit. And I'll
> take your advice and do some searching. I already had a good read
> through of some of the more recent posts and found some invaluable
> info in there.
> 
> Is it necessary to replace the IC's if the traces are being taken 
care
> of? it *looks* like it's in good shape, but I guess looks can be
> deceiving.
> 
> I will also note that the Effects section seems to be working just
> fine now.
> 
> 
> --- In PolySix@yahoogroups.com, "gil_we" <gil_we@> wrote:
> >
> > There' a lot of info about these type of problems on the archives,
> > just search ;)
> > 
> > Basically what you have is an acid eaten board (KLM367),
> > you need to retrace and replace the ICs around the battery area.
> > 
> > I must say that although I already fixed a few, the last one was a
> > pain and I ended up returning it to the owner. I fixed most 
problems
> > except for the memory selector which was acting strangely, again 
check
> > the archives.
> > 
> > --- In PolySix@yahoogroups.com, "mydadvsyours" <arturo00@> wrote:
> > >
> > > Hey there. I'm in the process of fixing one of my polysixes. I'm
> > pretty close to complete. I 
> > > have a few remaining issues and was just wondering if any of you
> > could tell me exactly 
> > > where/what on the KLM-367 board I'd need to fix in order to get
> > these issues resolved. (I 
> > > know that most of the problems revolve around the 7408's at 
IC31 and
> > IC32...). As 
> > > mentioned, I have another polysix that i'm using for parts and 
have
> > pretty much swapped 
> > > all of the boards...and the problems mentioned above are still
> present.
> > > 
> > > Here are my problems:
> > > 
> > > - Chorus always on (no difference between either of the 3 
effects,
> > but speed/emphasis 
> > > adjustment still works)
> > > - Bank D and Program 4 or 5(?) lights stay on all the time
> > > - VCO selector only outputs Sawtooth and PWM waveforms
> > > - Attenuator doesn't do anything (but the EG selector seems to 
work
> > ok...now!)
> > > - Mod wheel has no effect
> > > - The memory section is a little wonky
> > > 
> > > So yeah, any help or suggestions would be greatly appreciated...
> > > 
> > > Arturo.....
> > > 
> > > ps. Also, i'd like to not have that second polysix goto waste. 
does
> > anyone know if its 
> > > possible to use the circuit boards for other applications (ie.
> > external filter, wave generator,  
> > > etc). If you know of any sites that show how to frankenstein 
polysix
Show quoted textHide quoted text
> > modules, lemme 
> > > know!
> > >
> >
>

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