Those little RF boxes don't really convert from composite to RF, they
just provide a switch and a connection to a TV antenna input. The
output signal from the computer is already RF. Actually, what I
generally do with machines that have RF out only (i.e. Atari 2600) is
to just go to Radio Shack and get an RCA to F type screw connector
adapter. It's much smaller, and gives much better picture than those
little metal boxes do. It just doesn't provide a switch. What I want to
do is to actually input a true composite video signal into the TV. Of
course, this can be done by using a broken VCR with A/V inputs and a TV
output, but I want to modify the set as a learning experience, as well
as to create something useful for old computers.
Ian Primus
ian_primus_at_yahoo.com
On Monday, June 30, 2003, at 09:17 PM, John Rollins wrote:
> I would think the easiest and cheapest way is to use a plain old RF
> modulator box that will put composite video on to channel 3 or 4. I've
> taken apart one or two and they seem to have little more than a few
> coils and small parts, a far cry from the rack mounted cable TV
> modulators I just picked up(ooohh... so many trimmer caps and
> coils...). I don't know a whole lot about it, but I'm slowly learning
> as my interest in fast scan ATV increases... The converter box I have
> goes with my TI-99, I probably have one in the box with my C-64, too.
> I think you can still get them at Radio Shack. Otherwise, all you need
> to do is dump the composite signal into an AM modulator and then
> through a transmitter that the TV can pick up. I would guess these
> small boxes having only coils just use a tuned circuit for channel 3
> and the voltage from the composite signal to provide the signal. But
> then I'm just guessing, I've never poked and prodded those little
> boxes very much, I think I'll go do that now(when I find it,
> anyhow...).
>
>
>> I have read a lot about the SWTPC TV Typewriter, and I am interested
>> in how people modified a black and white TV for a video monitor. I
>> have an old black and white set that I thought would be fun to modify
>> for use as a video monitor. Now, granted, I don't really need another
>> composite monitor, I have plenty of old Apple monitors that will do
>> the same thing, I just thought it would be fun, since it would be a
>> challenge to find where to input the signal and how to do it. I found
>> the PDF of part of the SWTPC TV Typewriter manual on a web site, and
>> it explains the process, although not in great detail, and references
>> a circuit diagram of what needed to be added, but the diagram is
>> nowhere to be found. Does anyone have any instructions or hints that
>> they may be able to give me? Has anyone done this before? Any advice
>> would be appreciated.
>
> --
>
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Received on Mon Jun 30 2003 - 20:48:00 BST