All about the Roland Jupiter-series

You can try "chill spray". This is available at some electronic 
supply houses (not sure about RatShack).

Heat up the JP, open it and use a 100watt lamp (not too close!). When 
it starts to malfunction, carefully spray the suspected voice (or 
other) chip, using a LITTLE spray at a time. If you spray too 
much/fast you could CRACK the device from thermal shock.

If there is no improvement, allow the just-sprayed chip to get back 
to oper/ temp, and move to the next one.

The theory is that if you have a thermal problem, the chill spray 
drops the chip temp to norm or below and it "works" normally again 
(as if it were cold and just starting up). Then, as the chip heats 
up, the problem reappears.

If the problem goes away when a particular chip is sprayed, it is 
probably thermally defective and you have found the problem.

Sometimes, just placing a finger on top of a chip will reveal that 
its running hot.

Before you do any of the above, put on an anti-static strap and 
carefully but firmly push down any socketed ICs. This may/should 
eliminate any thermal contact problems.

If you find a bad chip...you WON'T have an easy (or cheap) time 
finding a replacement, as almost all the JP chips are obsolete.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

--- In Roland_Jupiters@yahoogroups.com, "James Brinkhoff" 
<jamesb@i...> wrote:
> Hi.
> 
> I've got a problem with my 6. It only happens sometimes, and seems 
to 
> only happen when it's hot, or when it's been on for a while. 
> 
> One of the voices drops in and out, creating large "popping" 
noises. 
> This is always either voice 2, 4, or 3 - and often they drop out in 
> that order.
> 
> I've tried disconnecting and reconnecting all the connectors, but 
it 
> doesn't seem to have done the trick?
> 
> Any ideas?
> Thanks, James