Synth-DIY Yahoo! Groups Archives

Polaris after 15 seconds get all stopped like frozen

2014-08-25 by sukhoy27@...

Dear Paul ,

Please May you help me to understand why my Polaris , when turn on, after 15/20 sec it became frozen, and all push buttons do not respond , it seems that the sliders works good , when it start to froze!

This froze , start with last note continuing to play , and then if I try to change memory / patch the push buttons starts slightly not to respond , till everything stop, and even all push buttons don't respond !

Few days ago VCO 1 played with a fast glide , and I ordered a new chip CEM3374 .

I really do not know what to do ! Please May you give me some advice ?

Ciao

Mario

RE: [chromapolaris] Polaris after 15 seconds get all stopped like frozen

2014-08-26 by Paul D. DeRocco

> From: Mario
>
> Please May you help me to understand why
> my Polaris , when turn on, after 15/20 sec it became frozen,
> and all push buttons do not respond , it seems that the
> sliders works good , when it start to froze!
>
> This froze , start with last note continuing to play , and
> then if I try to change memory / patch the push buttons
> starts slightly not to respond , till everything stop, and
> even all push buttons don't respond !
>
> Few days ago VCO 1 played with a fast glide , and I ordered a
> new chip CEM3374 .
>
> I really do not know what to do ! Please May you give me some advice ?

Are you saying that it fails gradually? Most freeze ups happen suddenly
and all at once.

The first thing to try on any old piece of electronic equipment is to
check all the connectors.
Open it up (with the power off) and unplug and plug all the connectors
(except the battery one, if you want to keep your memory). If the
integrated circuits are in sockets (most Polarises have sockets), you
could also try pressing on them to make sure they're properly seated.

It's also possible that the EPROMs are fading, since they're 30 years old.
This would cause the CPU to occasionally read a bit incorrectly, causing
it to strange things, or even crash. The solution to this is to erase and
reprogram the EPROMs, which can be done by anyone who has an eraser and
programmer. The hex files are available at the rhodeschroma.com web site.

Another frequent issue, if you have the old power supply, is the DC OK
threshold adjustment. But if this is set improperly, it should freeze the
Polaris instantly, not gradually. You can read about this in the Service
Manual, also available at rhodeschroma.com, on pages 3-22 and 6-1.

--

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

Re: [chromapolaris] Polaris after 15 seconds get all stopped like frozen

2014-08-26 by Bob Stewart

Sound like you might have a processor issue. Had a similar issue with a Roland JP6 recently, and needed a new processor chip.

:-(

On Tuesday, August 26, 2014, sukhoy27@... [chromapolaris] <chromapolaris@yahoogroups.com> wrote:

Dear Paul ,
Please May you help me to understand why my Polaris , when turn on, after 15/20 sec it became frozen, and all push buttons do not respond , it seems that the sliders works good , when it start to froze!

This froze , start with last note continuing to play , and then if I try to change memory / patch the push buttons starts slightly not to respond , till everything stop, and even all push buttons don't respond !

Few days ago VCO 1 played with a fast glide , and I ordered a new chip CEM3374 .
I really do not know what to do ! Please May you give me some advice ?

Ciao

Mario

Re: [chromapolaris] Polaris after 15 seconds get all stopped like frozen

2014-08-26 by sukhoy27@...

Dear Paul ,
thank You for very fast answer !
The frozing effect appears not immediately but gradually !
As You suggest It should Be the EPROM ( It's also possible that the EPROMs are fading, since they're 30 years old )
So I'll look forward to find good EPROM and rewrite the binary code into , downloading from the web site .
Today in fact I LowerFunction+D+12+STOP > and tune all, and Polaris start playing perfectly.

Probably because eprom reset ?

I'll also replace all Power Supply capacitors ( with new one 100° or 63V ), and re misure all the voltage outgoing !

I'll look after for uP at the end of the job.

Thank You very much Paul for Great efforts !!!

Ciao

Mario

From: Bob Stewart bob@... [chromapolaris] <chromapolaris@yahoogroups.com>;
To: chromapolaris@yahoogroups.com <chromapolaris@yahoogroups.com>;
Subject: Re: [chromapolaris] Polaris after 15 seconds get all stopped like frozen
Sent: Tue, Aug 26, 2014 6:05:17 AM

Sound like you might have a processor issue. Had a similar issue with a Roland JP6 recently, and needed a new processor chip.

:-(

On Tuesday, August 26, 2014, sukhoy27@... [chromapolaris] <chromapolaris@yahoogroups.com> wrote:

Dear Paul ,
Please May you help me to understand why my Polaris , when turn on, after 15/20 sec it became frozen, and all push buttons do not respond , it seems that the sliders works good , when it start to froze!

This froze , start with last note continuing to play , and then if I try to change memory / patch the push buttons starts slightly not to respond , till everything stop, and even all push buttons don't respond !

Few days ago VCO 1 played with a fast glide , and I ordered a new chip CEM3374 .
I really do not know what to do ! Please May you give me some advice ?

Ciao

Mario

RE: [chromapolaris] Polaris after 15 seconds get all stopped like frozen

2014-08-26 by Paul D. DeRocco

> From: Mario
>
> I'll also replace all Power Supply capacitors ( with new one
> 100° or 63V ), and re misure all the voltage outgoing !

Yes, that's a good idea too. The digital power supply may have ripple on
it, which could mess things up even if the average voltage looks good on a
meter. If you have access to a scope, you could see if there is any
ripple.

> I'll look after for uP at the end of the job.

I wouldn't buy a replacement CPU unless you have some specific evidence
that that's the problem.

--

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

RE: [chromapolaris] Polaris after 15 seconds get all stopped like frozen

2014-09-01 by sukhoy27@...

Grazie Paul.

Ciao