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polaris voice capacitors-- wont auto tune

polaris voice capacitors-- wont auto tune

2018-01-08 by wasteking1@...

i pulled out my 'spare' polaris from storage--- it had been fine last it was  played...and also has new membrane panels--but found  that now it wont play in tune--- and wont auto tune---  in fact as you go up the keys the intervals are odd and even play the same note on successive keys. According to other posts ,   I believe this has to do with bad voice capacitors on the main board.
Does this seem a likely diagnosis?  and if so,  what would the replacement capacitors be --
(type/value/ quantity)?   Would there be any other matters of concern  to replace them?


RE: [chromapolaris] polaris voice capacitors-- wont auto tune

2018-01-09 by Paul D. DeRocco

> From: wasteking1@...
>
> i pulled out my 'spare' polaris from storage--- it had been
> fine last it was played...and also has new membrane
> panels--but found that now it wont play in tune--- and wont
> auto tune--- in fact as you go up the keys the intervals are
> odd and even play the same note on successive keys. According
> to other posts , I believe this has to do with bad voice
> capacitors on the main board.
> Does this seem a likely diagnosis? and if so, what would
> the replacement capacitors be --
> (type/value/ quantity)? Would there be any other matters of
> concern to replace them?

It's almost certainly not the capacitors, because that would likely affect one channel first, and then maybe another one a year later, not all six at once. There's probably something wrong in the signal path that's common to all the channels. One likely place to look is the wires that carry the ALT OUT signal from the main board up to the output board, and the SYNTH ZCD line back to the main board. Connectors are always suspect. But this is the type of thing that isn't easy to diagnose without a scope.

--

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

Re: RE: [chromapolaris] polaris voice capacitors-- wont auto tune

2018-01-13 by steven pistrich

tjhanks----ill try to check that next week---- i do have a scope, but am a rookie with it......  ill update  soon



On Monday, January 8, 2018, 7:20:05 PM EST, 'Paul D. DeRocco' pderocco@... [chromapolaris] <chromapolaris@yahoogroups.com> wrote:


 

> From: wasteking1@...
>
> i pulled out my 'spare' polaris from storage--- it had been
> fine last it was played...and also has new membrane
> panels--but found that now it wont play in tune--- and wont
> auto tune--- in fact as you go up the keys the intervals are
> odd and even play the same note on successive keys. According
> to other posts , I believe this has to do with bad voice
> capacitors on the main board.
> Does this seem a likely diagnosis? and if so, what would
> the replacement capacitors be --
> (type/value/ quantity)? Would there be any other matters of
> concern to replace them?

It's almost certainly not the capacitors, because that would likely affect one channel first, and then maybe another one a year later, not all six at once. There's probably something wrong in the signal path that's common to all the channels. One likely place to look is the wires that carry the ALT OUT signal from the main board up to the output board, and the SYNTH ZCD line back to the main board. Connectors are always suspect. But this is the type of thing that isn't easy to diagnose without a scope.

--

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

Re: [chromapolaris] polaris voice capacitors-- wont auto tune

2018-01-14 by Gregory Cox

Just want to interrupt and say thanks Paul you’ve saved me some headaches once again.  I shelved my polaris for a while because I was stumped on some tuning issues I couldn’t figure out.  A few months ago I was spending way too much time trying to investigate this.  I read your suggestion below and today I popped it open and reseated all connectors to and from the output board and in a matter of minutes my polaris is back in tune… I swear, the only time the whole “reseat the connectors”, or “reseat the IC” has ever worked for me was when I was trying to fix an issue on my polaris lol.  Thanks again.

Greg



On Jan 13, 2018, at 8:58 AM, steven pistrich wasteking1@... [chromapolaris] <chromapolaris@yahoogroups.com> wrote:


tjhanks----ill try to check that next week---- i do have a scope, but am a rookie with it......  ill update  soon



On Monday, January 8, 2018, 7:20:05 PM EST, 'Paul D. DeRocco'pderocco@... [chromapolaris] <chromapolaris@yahoogroups.com> wrote:


 

> From: wasteking1@... 
> 
> i pulled out my 'spare' polaris from storage--- it had been 
> fine last it was played...and also has new membrane 
> panels--but found that now it wont play in tune--- and wont 
> auto tune--- in fact as you go up the keys the intervals are 
> odd and even play the same note on successive keys. According 
> to other posts , I believe this has to do with bad voice 
> capacitors on the main board.
> Does this seem a likely diagnosis? and if so, what would 
> the replacement capacitors be --
> (type/value/ quantity)? Would there be any other matters of 
> concern to replace them?

It's almost certainly not the capacitors, because that would likely affect one channel first, and then maybe another one a year later, not all six at once. There's probably something wrong in the signal path that's common to all the channels. One likely place to look is the wires that carry the ALT OUT signal from the main board up to the output board, and the SYNTH ZCD line back to the main board. Connectors are always suspect. But this is the type of thing that isn't easy to diagnose without a scope.

-- 

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