Re: Vic 20 RF Modulator

From: Scott McDonnell (
Date: 2002-10-02 07:22:34

----- Original Message -----
From: "Marko Mäkelä" <>
To: <>
Sent: Tuesday, October 01, 2002 2:42 PM
Subject: Re: Vic 20 RF Modulator
> On Tue, Oct 01, 2002 at 07:58:23PM +0200, Christer Palm wrote:
> > With a bit of soldering you can, of course, also use any suitable RF
> > modulator as a replacement.
> But where can you find such modulators?  Not all modulators operate on
> a composite video signal.  I have the opposite problem, trying to get
> composite video output (or S-video for that matter) from an Atari VCS

Basically both problems go hand in hand. Nearly EVERY modulator either
accepts luma/chroma or composite video for the input. This is because a
modulator does exactly what it is named; it modulates a compositie signal by
simply adding composite video signal and line-level audio signal directly
into a Chan 3 or 4 carrier frequency. If a modulator accepts a luma/chroma
signal, it is going to convert that into composite video before adding it to
the channel carrier.

Going from Luma/Chroma to composite is fairly simple. It is just a capacitor
buffer on the chroma line terminating into the Y and C lines tying together.
or for a deeper understanding and even more circuits:
(might want to bookmark

A google search for "Atari 2600 composite" resulted in this site.
If you are not comfortable with modifying your Atari, you could use a VCR to
do this for you.

However, to the original poster of this question: I would say to get your
hands on some kind of monitor with composite inputs, purchase a
fully-packaged modulator directly (read: no soldering required) from an
electronics retailer. Here in the states they go for around $20 USD at Radio
Shack. I'm sure you have some similar shop in your local area.
Of course, this does not solve your problem of not being confident with a
soldering iron, because you will still need to make a DIN to RCA cable. You
might look into it though, because it is extremely trivial to do (and if you
get crimp-type connectors, you do not even need to solder.)

> Another idea: if you want a Commodore to Scart cable but don't want to
> solder, get one of those cheap RCA (or RCA/Mini-DIN) to Scart adapters and
> a DIN to 4 RCA plugs cable.  (Or a DIN to 2 RCA plugs cable, in which case
> you probably will have to reroute one of the wires going to the DIN plug.)
> Marko
>        Message was sent through the cbm-hackers mailing list

       Message was sent through the cbm-hackers mailing list

Archive generated by hypermail 2.1.4.