Modding a Sega Genesis Model 2 video output

SO. Here goes a long, long post with everything I can think of to mention, so please bear with me on this. Also, please not pictures will be taken and uploaded later today as I'm typing this while on break at work.

I am now looking into modding a Sega Genesis that has come into my possession. I own a little bundle of games, two controllers, a Model 2 Genesis (NTSC, Canada), A model 2 AV-out-to-coaxial cable box, and a power adapter. No 32x, No Sega CD. The system is also not modded in any way (currently) and is in perfectly good condition. I figure that if someone might want to help point me in the right direction, I should state exactly what I have and am working with right now.

Condition of the system:

The genesis is aesthetically great, and the PCB has solid connections all over, with a small re flow done with myself on each contact point with a soldering iron and some flux just to make sure everything was good. All contact points are clean, and the system looks and works great.

Condition and description of the AV out port and cable:

The system is 3rd-hand now as my friend Simon got it as a hand-me-down when he was a kid, and I have bought the system off him so I do not know what happened but the AV port looks like it was exposed to far too much heat at some time; it looks as though the jack on the genesis has been either chewed somehow or fire messed up the plastic around the holes where you insert the AV cable. However, I have taken a very small Phillips screw driver and gently pushed it through the holes to clear up and fix the shape of the tiny sockets to make sure the video cable can be inserted fully and without force. The socket DOES in fact work and outputs audio and video as it should.

Now, the cable is an s-video looking plug on the end that plugs into the Genesis AV-out. The difference is that there are only 3 pins in the plug, which I am certain are Video out, Audio left and Audio right. As there are only 3 shiny pins inside a shiny metal circle I could not tell you for certain which one is video, and which two are audio. However, two of the pins are closer and stand straight up, while the other pin comes out into the socket on a 90-degree angle, facing the sockets side first then facing up, separated from the other two so I am going to make a pretty good guess and say that this is the video plug. Any-who, the cable runs 3-4 feet before coming to a black automatic switch box with Antenna in and a switch for Channel 3 and Channel 4 selection. There is an other wire leading out of this box which is permanently attached (like the AV out) and ends in a Coaxial output which could plug into darn well any type of television.

Something to note, also is that I do not understand fully the difference between Analog and Digital signals. Can craptastic Coaxial handle digital and analog? The only thing I know for certain is that Analog and Digital have two different signal types, with Analog signals being more rounded and Digital having more of a square wave. (http://www.hometheaternetwork.com/pics/ ... es_Analo...).

Assuming that Coaxial is capable of transferring Digital and Analog signals, does any certain type of Coax. only support analog output? Does digital have less video noise than say Analog output would? I'm off on a tangent about coaxial now, aren't I.

Finally, coming down to the real point is why I am making a video output mod and I want to verify that this can work and if it does then I think it would be a good thread for future noob modders to look at before trying their hand at a mod.

Keep in mind that while I am not too knowledgeable in Coaxial and signal technology, I am a geek so I'm not a tech Noobasaurus-Rex; I just really need some help starting this so I don't botch a beautiful old Genesis system. I have experience working on computers and mobile electronics and have taken tech courses, electronics courses and work on this stuff. This hobby is a great passion of mine, and I love to expand into areas I haven't learned about so the point I am trying to make is that I have not done this kind of tech work before (hard modding a system), but am also not a total noob so please bear with me.

Now. The reason I am looking into modding my Sega Genesis model 2 system is because as I have stated, the only audio visual output on this baby is a strange S-video type of plug that outputs to Coaxial audio video. My experience with Coaxial output from consoles has been terrible, as they are very sensitive to a cable being wiggled, and have a ton of video noise. The audio isn't horrible, but I feel that a switch away from Coaxial could certainly improve the quality a little by keeping these wires separated. I'm thinking that by having all these signals output on one pin, the left audio, right audio, and video signals are creating a bit of interference which would be expected with a design like this. This is why we have outputs like HDMI, Component, Composite, S-Video etc; to keep the signals all separated from each other to keep interference out and keep the signals as un-tainted and clear as possible.

With coaxial on all my systems, but most annoyingly with my Genesis the video is very fuzzy, colors blend into each other slightly, edges shake a bit from noise and are blurry. My atari does this too, but everything is like..solid squares on that so Im not so worried about an Atari being low-def and so I don't care. However games like Sonic 2 for example suffer from sonic looking very un-detailed and a little difficult to make out, the solid colors of the grass and sky have video noise all over them, yellow lettering up in the top of the stage where colors go by them causes slight rainbowing and fuzzy edges on the score / rings, and most of all the lack of clarity is just painful. My SNES had this very same problem when using Coaxial output, but when I plugged in the Composite (Red, White, Yellow) cable, the video was pretty clear and audio was just fine (video was only surpassed by my Super Nintendo's S-video output which made everything look brilliantly vibrant and sharp). I want to re-create some of that image fidelity with my Genesis by...

Adding in 3 Composite output ports. Yep, that's my plan. I would like to find some wires, some Composite input plugs to stick into self-made holes on the back of the genesis system and use them to keep audio left and right and video all separated from each other. I don't figure it should be too much hassle because as previously stated, it appears the genesis outputs the signals to the Coaxial in much the same way before it is all mixed down to a single-pin output to the television.

Now I am going to have to break the genesis down again to check how many pins are soldered under the AV input port for audio and video to see what there is and where it leads to on the PCB. What I am planning on doing is using some wire (if anybody has suggestions for type / gauge that would be good) to solder down to the connections where the current AV port is and lead them to their respective Composite output pins. I will of course be putting 3 small holes to slip the plugs into the back so that you can just plug the composite into the back of the genesis as you would any other cable) with a small circular saw bit for a drill, or just a very large drill bit if need be.

Here is a list of tools / surfaces I have access to for working with / on / at:

Tools:

Access to a soldering iron with adjustable temperature nob, and a soldering pen that just gets as hot as a resistor inside the handle of the pen must allow. (Just a cheap one).
A good heat gun with a narrowing tip on the end to focus the air into a more specific area, along with other tips and also a high and low setting.
Plenty of solder to work with on a spool.
Electric drill with a large selection of bits ranging from minuscule to the size of penny or slightly larger with MANY different sizes between.
Screw drivers of various types
hammers and crap of course
thumbtacks, sticky tac, super glue, screws, nails, etc...

Areas:

Inside and outside of my house of course.

Work spaces:

Inside the house in a workroom on a large wooden workbench with sheet metal covering the entire surface

Concrete floor of the workroom with plenty of open space.

Outside on gravel or a wooden table.

I'm mentioning this because if you have recommendations for where I should do this please let me know. (In case I need to hold components in with toxic-fume-adhesives that react when you mix them, best idea for a work area when working with a heat gun, etc..). Again, I have done electrical and work like this before, but this genesis is precious to me and if someone has the time / will to answer even a portion of all I have mentioned that would be fantastic. I just want to take precautions to do every detail right so I don't fry this thing.

I will take pictures and post them here of the genesis and its internals along with close-up shots of crucial connections within the genesis when I am done at work today.

So, if you read through that huge mess of unorganized but very informative text, what do you think? Anything I should know / you can fill me in on? Suggestions? Ideas? Anything?

Thanks for reading!
 
If you want composite jacks, then:

pinout3wy.jpg

source: g-force

http://www.gamesx.com/avpinouts/genesisav.htm and http://forums.benheck.com/viewtopic.php?f=35&t=31554. Personally I prefer something like this over the composite jacks, but a personal preference, I'm sure.

You can also do Svideo, but I can only find links to doing so on the Gen3 atm so no links to that as of now.
 
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