[sdiy] ems vcs3

[Magnus Danielson]

From: tania gallagher <tania.gallagher at pandora.be>
Subject: [sdiy] ems vcs3
Date: Sat, 23 Aug 2003 13:53:03 +0200

> hallo,

Hi,

> ik heb een probleem met mijn ems vcs3. Sinds kort zit er een brom op die
> bovendien ook alle oscillators distorted doet klinken. wanneer ik de machine
> aanzet begint hij meteen te brommen. Ik heb al een mail gestuurd naar ems,
> waar ze me aanraden de power supply te checken. waar en hoe begin ik best te
> meten? alle ideeen zijn meer dan welkom
> 
> groeten 
> 
> bart demey

While my knowledge in dutch is say restricted, my native language Swedish,
with some knowledge in German and English helps be decode this message...

Basically, there's hum all over, and all the oscillators distorts.

I've seen this first hand before on a Synthi A and the number one suspect is
the electrolytic caps at the diode-bridge in the powersupply. What has happend
is that they got old (as they tend to do) so that they no longer has the power
to hold the voltage up until the next peak. Replace them with new capacitors
of same capacitance and voltage. There are neat high temperature ones which
can handle heat a little better than the old ones did.

You should also consider replacing all the other caps, but do start with these
two. It's quickly done and cheap enought to do.

PS. This is a English-speaking list ... most of the times...

Cheers,
Magnus