Jump to content
IGNORED

Sega Genesis Model 1 s-video option


AMenard

Recommended Posts

Ah ok.

 

I'll look into that mod or trade it for a model 2.

 

S-video doesn't exist on the model 2 either. ALL models of the Genesis and MD by extension have to be modded for S-video. Very easy to do for the most part and if you remove the RF modulator, then you can mount the s-video through the opening that the RF out used. But you would require a washer or something to hold it because the opening is just a bit too large for most s-video panel jacks. Could also enlarge the opening where the channel select switch is on the back of the model 1 to add your s-video jack there as well.

 

While it is always fun to make everything yourself, this is the easiest and overall cheapest solution I use:

 

https://console5.com/store/cxa1145-s-video-and-composite-video-mod-pcb.html

 

In that link you can buy a premade PCB for the components, plus the components, plus jacks and hookup wire if needed. I like that Console5 did this on this particular item in that you can only order exactly what you might need.

Edited by -^Cro§Bow^-
Link to comment
Share on other sites

S-video doesn't exist on the model 2 either. ALL models of the Genesis and MD by extension have to be modded for S-video. Very easy to do for the most part and if you remove the RF modulator, then you can mount the s-video through the opening that the RF out used. But you would require a washer or something to hold it because the opening is just a bit too large for most s-video panel jacks. Could also enlarge the opening where the channel select switch is on the back of the model 1 to add your s-video jack there as well.

 

While it is always fun to make everything yourself, this is the easiest and overall cheapest solution I use:

 

https://console5.com/store/cxa1145-s-video-and-composite-video-mod-pcb.html

 

In that link you can buy a premade PCB for the components, plus the components, plus jacks and hookup wire if needed. I like that Console5 did this on this particular item in that you can only order exactly what you might need.

Thanks! Exactly what I needed. Ordered one.

Link to comment
Share on other sites

Let me know if it works out for you, because I got nowhere with mine. Kinda disheartening. I don't know if there was something wrong with my Genesis or if I just suck at soldering. I mean, it could be both, but I followed the directions and couldn't get a picture out of it! Tres disappointing.

Link to comment
Share on other sites

Let me know if it works out for you, because I got nowhere with mine. Kinda disheartening. I don't know if there was something wrong with my Genesis or if I just suck at soldering. I mean, it could be both, but I followed the directions and couldn't get a picture out of it! Tres disappointing.

 

I have found that some model 1 systems actually have the video encoder mounted in the other direction. The last one I did I couldn't figure out why it wasn't working because I'd done quite a few these over the years and was confused. Then I noticed that the notch on the 1145 was facing towards the back of the console and not the front?! It was then I realized I had soldered everything to the wrong side! BTW..this was just last month and I was surprised at this and hadn't even noticed it was mounted opposite since I'd done so many of these I hadn't even noticed.

 

Luckily it didn't cause any damage, but did make me have to start checking them more in the future. This was on a va6.5 model 1 as I recall.

  • Like 1
Link to comment
Share on other sites

I think I was paying attention to where the notch was, although at the same time I was soldering on the underside of the board, so that may have complicated things. I got a lot of assistance from Luke at Console5, and sent him pictures of the board as I worked on it. It seems like he would have told me if I had made that mistake.

 

What's weird is that I tried to connect my system to a VGA monitor using the pins under the A/V port, and could not get it to work with a single monitor... not even the two described as 15khz compatible in the list compiled by Amiga computer owners. You're supposed to add 75ohm resistors on the R, G, and B lines, but that was just to reduce the color brightness. I figured I would get SOME kind of picture out of those monitors, but never did...

Link to comment
Share on other sites

The euro megadrive have rgb on the video out for use with a scart cable. I wonder if the NA have it too? If the do, a scart cable and a scart to hdmi could give us the best out of the model 1..

 

Yes, in fact the Genesis is often the "gateway" for most of us into the RGB/SCART realm! I would skip S-Video and just take the native RGB and convert to component or HDMI.

Link to comment
Share on other sites

The euro megadrive have rgb on the video out for use with a scart cable. I wonder if the NA have it too? If the do, a scart cable and a scart to hdmi could give us the best out of the model 1..

 

Yeap...sure does.

 

I started out with s-video on my Genesis and still add this to Genesis consoles when I get them in because the s-video does look really good as well. But now I use HDretrovision cables from my Genesis and won't likely ever go back. I even like the picture quality I get from them over the RGB Scart cables I have for the Genesis through the OSSC. The RGB looks good too, but the image is a tiny bit darker through the RGB setup vs the HDretro cables.

 

I think I was paying attention to where the notch was, although at the same time I was soldering on the underside of the board, so that may have complicated things. I got a lot of assistance from Luke at Console5, and sent him pictures of the board as I worked on it. It seems like he would have told me if I had made that mistake.

 

What's weird is that I tried to connect my system to a VGA monitor using the pins under the A/V port, and could not get it to work with a single monitor... not even the two described as 15khz compatible in the list compiled by Amiga computer owners. You're supposed to add 75ohm resistors on the R, G, and B lines, but that was just to reduce the color brightness. I figured I would get SOME kind of picture out of those monitors, but never did...

 

Well Luke knows his stuff so the only other possiblity I can think of is that there could have been something physically wrong with the 1145 in regards to the luma output from the chip? The s-video mod on the genesis is really quite straight forward. So if you weren't getting any picture from that same kit, then you have to start with making sure you are getting power to it..etc. I've used that same kit I linked to well over a half dozen times since he started offering it up in a piece as you need method.

 

As for the VGA, the genesis doesn't put out H-sync and V-sync which are required for VGA output. I believe the Genesis uses C-sync for the RGB out.

Link to comment
Share on other sites

I thought only composite sync was needed for the VGA mod. It's just picky about which monitors it will work with, since it outputs a 15khz signal and many displays won't take it.

 

It's possible the Genesis was damaged in some way... it was a yard sale rescue in pretty lousy shape. Luke sent me two chips (one experimental and another standard) and neither functioned. I didn't think to test luma with a multimeter, but you would think if it wasn't working, you couldn't get a picture at all out of the system. Composite and SCART both work, though! (shrugs)

Link to comment
Share on other sites

  • 4 weeks later...

Except for the two Wondermega models which have S-video out of the box...

 

I forget about that specific model. Likely because they go for prices WAY above what I can convince myself to pay for a retro console LOL.

 

How about the laser active? I assume it has an s-video output as most LDs did back then so I assume it would count as having s-video out.

Link to comment
Share on other sites

for what its worth, I have recently done a S-VIDEO and composite and its not playing nice with modern HDTV's due to the signal strength being about half of what it should be

 

I hooked my particular unit (a model 1 VA2) up to the scope and dialed in where its ~1v peak to peak including sync but its not going to be the same over every revision of the pcb as its not even in spec from the factory ... but in the late 80's early 90's if one had the luxury its analog processing was more tolerant like many other systems

 

which also goes to show that a generic canned response on how to do XYZ doesnt always work ... even if it did in 2002 on a sony ABC model TV, engineering a proper signal is more than cooking up a canned response and hoping for the best, it requires measurement and repeatability

 

NTSC should be a 0.3 to 1 volt video signal (leaving 0.7 volts for luma data) with a 0.3 to 0 sync signal just fyi according to RS170 (original black and white tv in the USA) standards with about a 0.2v colorburst reference at the end of the "rear porch"

 

your standard issue canned used these 3 radio shack parts mod instructions cut that to about 0.4 volt signal and 0.15 sync data which work fine in sloppy old TV's but not so much on nit picky modern ones

Edited by Osgeld
Link to comment
Share on other sites

for what its worth, I have recently done a S-VIDEO and composite and its not playing nice with modern HDTV's due to the signal strength being about half of what it should be

 

I hooked my particular unit (a model 1 VA2) up to the scope and dialed in where its ~1v peak to peak including sync but its not going to be the same over every revision of the pcb as its not even in spec from the factory ... but in the late 80's early 90's if one had the luxury its analog processing was more tolerant like many other systems

 

which also goes to show that a generic canned response on how to do XYZ doesnt always work ... even if it did in 2002 on a sony ABC model TV, engineering a proper signal is more than cooking up a canned response and hoping for the best, it requires measurement and repeatability

 

NTSC should be a 0.3 to 1 volt video signal (leaving 0.7 volts for luma data) with a 0.3 to 0 sync signal just fyi according to RS170 (original black and white tv in the USA) standards with about a 0.2v colorburst reference at the end of the "rear porch"

 

 

I take it you didn't use this kit then?

 

https://console5.com/store/cxa1145-s-video-and-composite-video-mod-pcb.html

 

I was making up this same circuit on PCB for a while and that is why I prefer to use the variable resistors to dial in a particular system to my TV etc.

Link to comment
Share on other sites

trimpots drift over time and heat changes (which is why you see blobs of glue on them in commercial electronics)

 

and I am cheap, and capable so no I did not spend 5 bucks + postage for a pcb I could have had 10 made for me in about 2 weeks from china

 

so i just tuned it in with a trimpot and a bit of math took those values to what I had on hand (which is a nearly complete set of 1%'s) and locked them in

Link to comment
Share on other sites

Well to me the cost of the PCB and the parts in a kit is worth it to me to not have to lay everything out on a PCB and hand solder it together as I was doing originally for several years. LOL.

 

eitherway, I've had excellent results with the kit and never had any issues getting it to display on a TV properly. Though I'm surprised you stated the composite signal was weak because that is actually built into the system to use through the AV cable out the back. I admit the composite on the model 1 genesis has always been crazy blurry but usually looks fine otherwise? But that kit above also includes stuff to clean up the composite a little and trimpot to dial that in as well.

 

I like the trimmers because adjusting the luma, you can greatly reduce the jail bars on the s-video. Oh..and running the chroma and luma wires from the board to go outside the RF shielding and away from that 3515 VDP chip helps a lot as well.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...