S-Video conversion possible as plug-and-play solution?

Modding and Technical Issues

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Kakemoms
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Re: S-Video conversion possible as plug-and-play solution?

Post by Kakemoms »

Just as a last note: If you buy the chinese grabber, it will stop working due to some problems with the driver after a while. :shock: I ended up downloading an alternate driver (see here for troubleshooting and alternate driver), but it didn't get the Honestech software to work again. So I ended up using the Open Broadcaser Studio (free software) instead. As a plus you can then re-size the Vic-20 video window freely. :mrgreen:
repetto74
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Re: S-Video conversion possible as plug-and-play solution?

Post by repetto74 »

Received the kit from Mike and set this up in a second. Here is the result. Awesome! :D
Never saw a so crisp Vic-20 prompt in my entire life :shock:

Thank you!
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mrr19121970
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Re: S-Video conversion possible as plug-and-play solution?

Post by mrr19121970 »

You should let to dupont connector dangle out through the dataset port and secure to the main board with a cable tie on the eyelet between data settle edge connector and iec port.
repetto74
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Re: S-Video conversion possible as plug-and-play solution?

Post by repetto74 »

Ok mrr19121970 thanks I'll do that :wink:
oggie
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Re: S-Video conversion possible as plug-and-play solution?

Post by oggie »

So I built one of these, but for some reason I'm only getting black and white display. The only differences were I used a 330 ohm resistor instead of a 360 because I didn't have one handy.... That shouldn't make it completely b&w, should it?

If so, I'll have to see if I have a 30 ohm somewhere to wire in series.
oggie
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Re: S-Video conversion possible as plug-and-play solution?

Post by oggie »

oggie wrote:So I built one of these, but for some reason I'm only getting black and white display. The only differences were I used a 330 ohm resistor instead of a 360 because I didn't have one handy.... That shouldn't make it completely b&w, should it?

If so, I'll have to see if I have a 30 ohm somewhere to wire in series.
I was just thinking... the order of the resistor and capacitor in series probably matters, right? so which is it?

IC pin2 ->cap->resistor->svideo chroma or
IC pin2 ->resistor->cap->svideo chroma ?

I think mine is the former... it's all covered in heat shrink, so I can't remember.
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mrr19121970
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Re: S-Video conversion possible as plug-and-play solution?

Post by mrr19121970 »

cap 1st
oggie
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Re: S-Video conversion possible as plug-and-play solution?

Post by oggie »

cap 1st? Cap to pin 2 first, or cap to svideo cable first?

Looking at the post here, http://sleepingelephant.com/ipw-web/bul ... 793#p85393 the resistor should be 1st (attached to pin2 of the vic).

Right now, I have the cap attached to pin 2.
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akator
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Re: S-Video conversion possible as plug-and-play solution?

Post by akator »

I bought this upgrade last year but life got in the way and I didn't get a chance to install it until today. What an amazing difference this makes for displaying on a modern HD display!

I highly recommend it. Buy it if it's still available, and if not build the mod yourself. The parts are all easily purchased, even on Amazon, so everyone should be able to have S-video on a VIC :)
naujoks
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Re: S-Video conversion possible as plug-and-play solution?

Post by naujoks »

I'm succesfully using this mod with my Sony PVM monitors and the pictures is perfect, it couldn't be any better.
I recently got a Commodore 1084S-D1 monitor but with it I only get an extremely distorted picture, it looks like a sync issue.
Any idea what the reason for that could be?
mathop
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Re: S-Video conversion possible as plug-and-play solution?

Post by mathop »

Bit late to the party. It appears the S-Video mod being talked about here takes the chroma directly off the chip, albeit with a resistor + cap in between. This does not feel right to me. Should there not be a proper buffer/amplifier in between? I.e. similar to how the C64 modulator operates.
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Mike
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Re: S-Video conversion possible as plug-and-play solution?

Post by Mike »

mathop wrote:It appears the S-Video mod being talked about here takes the chroma directly off the chip, albeit with a resistor + cap in between.
FYI, here is the original thread that started it all in 2008: S-Video from the VIC
This does not feel right to me. Should there not be a proper buffer/amplifier in between?
That's what I did ... :wink: ... see here: http://sleepingelephant.com/ipw-web/bul ... 7&start=90

...

The "plug-and-play solution" as asked for in the OP is anyway only possible when VIC is socketed. When the video chip is soldered in, at least one permanent change of the video circuitry is necessary to prevent the mixing of luma and chroma in first place, even if as small as cutting the ferrite bead (like in Boray's "Simplest s-video mod ever for Vic-20CR").

OTOH, the original video circuitry could be considered broken by design: a proper S-Video mod cures that fault and warrants solder work on the mainboard anyhow. :)
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JonBrawn
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Re: S-Video conversion possible as plug-and-play solution?

Post by JonBrawn »

Mike wrote: Wed Dec 27, 2023 9:58 am OTOH, the original video circuitry could be considered broken by design: a proper S-Video mod cures that fault and warrants solder work on the mainboard anyhow. :)
There's a whole bunch (6? 8?) of different circuits used in different VIC-20s for video, so a one-size-fits-all S-Video mod is never going to cover all of them unless it starts with "isolate the Luma and Chroma as they come onto the PCB from the VIC" :-(
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