All about the Roland Jupiter-series

-----Original Message-----
From: kennyb@... [mailto:kennyb@...] 
Sent: Saturday, August 12, 2000 3:45 AM
To: analogue@...; prattwink2@...
Subject: Re: [AH] Jup 6 VCO help



> Does any one know if the 3340 used in the Jup-6 needs
> to be a modified chip (white dot mark on it)? My tech
> seems to think so. He put a normal 3340 in and could

I do not think that it is a modified chip. It should just
be a 3340. Perhaps someone else on this list can shed light
on the 3340 (Paul Schrieber perhaps????)

> not get it to tune. It is an issue because when my
> Jupiter 6  is in poly 1 mode, vco 2 skips a voice
> every sixth note played.

When you say skips a voice you mean does not play right?
It sounds like your tech figured out which voice board
and which voice is the problem right?

Now the problem is that you cannot tune that one voice with
the new CEM. I have a Jupiter-6 but have not yet had
this problem. I did however have exactly this problem on
my 6-Trak. One of the CEM's blew, I replaced it with
another and the voice was out of wack. I then replaced
it again and the third one was A-ok. The reason? The
second one was also blown or somehow blew while I was 
installing it but still kinda barely worked.

Does your tech have the full service manual and schematics?
The calibration on the Jupiter-6 is really really 
amazing! You just hit the button on the CPU board and
follow the steps. The service manual even tells you the
settings for the scope. Good engineering!

Cheers,
Ken