Apple I / II RF?

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bushnrvn's picture
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Apple I / II RF?

I just picked up a really fantastic Mitsubishi television manufactured August 1982. It only has the VHF/UHF connections. Is there any practical way to hook up a member of the Apple II family to this gem?

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Re: Apple I / II RF?

RF Modulator like the SupeR Mod, or a old VCR, with composite Video In, and use the RF out ( on channel 2 or 3 or 4 ).

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Re: Apple I / II RF?

Hello bushnrvn,

allthough the contents of the following mentioned page have not been translated yet
and therefor still are only availiable in German text at least the circuitplans could
be understood also from english speaking persons:

http://www.appleii-box.de/H003_FBASSYNCLIB.htm

in the lower part of the page the topic is treated how to add a FBAS / VIDEO signal input to
regular TV-set.
This was a common task that has been performed very often in the 80´s while
simple Monitors have been very expensive and most computers issued NTSC or PAL Video signal at
the video output...

Of course you might also use a UHF modulator similar to those mentioned above ...
but in fact often the modules don´t deliver good color quality....
there are different kinds of modules availiable sometimes in electronic stores:
some only good for b/w tv and some also labeled to be used for color tv-set...

sometimes some of the modules can be trimmed inside of the module for better quality...

but it´s also true that adding a standard video-signal connector to tv-set isn´t a task
for absolut newbies.... maybe a person within the circle of your friends has
some experience as tv-tecnician or similar knowledge....

at least it´s worth a short look....
sincerely speedyG

bushnrvn's picture
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Re: Apple I / II RF?

Would any old RF Modulator work? Say like an RF Adapter for an SNES paired with a IIgs? I'd just go ahead and test it but I am cautious about wrecking the circuitry - if that's even a possibility.

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Re: Apple I / II RF?

Hello bushnrvn,

in general it´s recommended to make the connection with a capacitor between the modulator and the computer.
This makes sure that no continuous current infiltrates in either direction one of the both components
by blocking such voltage.
The capacitor only permits the passing of alternating current like the videosignal.
In general the capacity of the capacitor should be something about 3µ3F.
The important thing is the voltage limitation of the capacitor: it should at least state limit of 350 Volt or higher.
In general lot less high limit is present ( less than 5 Volt ), but the higher limit is in cases some things go wrong the best protection.
Taking this precaution should give a excellent protection at both sides of the circuitry.
speedyG

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