RF modulator compatibitily btwn commodores

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komodorecomrade
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RF modulator compatibitily btwn commodores

Post by komodorecomrade »

Hello comrades!

would a amiga RF modulator like this one on ebay

Image work with a VIC? mine (NTSC) is kind of flaky,its a bit rusty & i have to wiggle it to get a good pic

actually my vic's video output goes through two tin boxes connected to each other. my monitor has an RCA AV input, anyone know what cable needed to connect the vic20 board connector direct to the AV input?

thx
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Pedro Lambrini
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Post by Pedro Lambrini »

As far as I know there is no way to use the Amiga modulator on the Vic. I presume you live in North America as you have an NTSC machine. If so, here's a link to an eBay BIN post:

http://tinyurl.com/cb8oxl

This lead goes straight from the 5 pin connector on the Vic to the RCA inputs on your monitor. Hope this is what you're looking for. :)
"...That of the Eastern tribe being like a multitude of colours as if a rainbow had settled upon its brow..." Daniels 1:3
carlsson
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Post by carlsson »

No, the A520 would not do you much good. To begin with I think it uses the RGB signal from the Amiga to form an RF signal while the VIC only has composite video to work with. Actually the A520 has a composite video output. The two boxes you refer to probably is a RF modulator followed by a switch box.

As to your second question: you can either solder your own cable or buy one on eBay etc. The VIC-20 has composite video and mono audio output, so it is only a matter of soldering three pins (audio, video, ground) on a 5-pin DIN and then RCA plugs in the other end.

http://pinouts.ru/Video/Vic20Video_pinout.shtml

The pins you want to use are Audio (3), Video Low (4) and Ground (2). In that way, you will be able to use the same video cable also for any C64, Atari 8-bit and a couple more systems which share mostly the same pinout.
Anders Carlsson

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shem
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Post by shem »

Yes the a520 modulator is not suitable for a vic or 64 or c16 etc
the a520 use rgb converts it the vic and other 8 bit machines use composite video your best bet would be a din to rca ebay i guess when i had an amiga i found that the modulator never gave the best picture quality so i soon got a scart cable
I'll take my cart to go thank you ;)
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ral-clan
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Post by ral-clan »

anyone know what cable needed to connect the vic20 board connector direct to the AV input?
We desperately need to make the "VIC video cable hack" into a DenialWIKI article, and "sticky" a link to the top of the general topic thread.

I think this is the third time this question has been asked in the last two months - and there are probably a dozen duplicate threads with the same question & answers as above here on Denial.
komodorecomrade
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Post by komodorecomrade »

the third time? :oops:

maybe more modulators fail in the winter?

thanks for the ebay link pal! thats exactly what i wanted. i looked at the pinout too. very simple. i thought the vic output a VHF channel frequency not composite output.i guess those RF tin boxes do all the magic then.
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Pedro Lambrini
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Post by Pedro Lambrini »

^
You're welcome. :)

And, yes, those little tin boxes are truly magical. If you look into the wee RCA socket sideways sometimes you can see a fairy inside painting blocky pictures... :P
"...That of the Eastern tribe being like a multitude of colours as if a rainbow had settled upon its brow..." Daniels 1:3
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amramsey
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Post by amramsey »

carlsson wrote:As to your second question: you can either solder your own cable or buy one on eBay etc. The VIC-20 has composite video and mono audio output, so it is only a matter of soldering three pins (audio, video, ground) on a 5-pin DIN and then RCA plugs in the other end.

http://pinouts.ru/Video/Vic20Video_pinout.shtml

The pins you want to use are Audio (3), Video Low (4) and Ground (2). In that way, you will be able to use the same video cable also for any C64, Atari 8-bit and a couple more systems which share mostly the same pinout.
Alrighty, I picked up a Vic-20 for parts this weekend off Kijiji and it came with an RF box that just won't work. I had another one in the same condition so I cut off the RF box and used those cables to connect directly to RCA cables. Thanks for the post, told me exactly what I needed to know to make the cables! :D

Now I need to tweak the Vic-20 to get true colours I suppose. Most of the colours looks ok-ish except white (and possibly yellow). White appears as a grey. :x

Any hints on where I need to tweak on the vic-20 board itself to fix the colours? :)
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ral-clan
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Post by ral-clan »

There's a wonderful thread here on Denial with pictures. It should be made into a permanent Wiki article. If you do a search on "pot adjustment" or something like that you should find it.

EDIT: Here is the thread but it looks like Schema removed the nice pictures. Did anyone save them?

http://sleepingelephant.com/ipw-web/bul ... ot+monitor
Richard James
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Post by Richard James »

I did the same thing with the RF adapter. Cut it up and created a video and sound out. Then I soldered it and used shrink wrap to seal it.

I did not take pictures because mine was a very amateur effort. The only problem I had was to work out which was sound and which was the 5V line. I used a multimeter while the VIC20 was turned on.
Change is inevitable except from a vending machine.
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ral-clan
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Post by ral-clan »

Actually, the pictures in the thread linked to above were of the colour & sharpness pots inside the VIC-20.
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amramsey
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Post by amramsey »

ral-clan wrote:Actually, the pictures in the thread linked to above were of the colour & sharpness pots inside the VIC-20.
I'll crack my vic open again tonite and start twiddling my pots. Thanks for the hints guys! :D
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