S-video mod

[jaxmazon]

Hi guyz I found out about a megadrive 1 s-video mod and im really interested in doing it but I not sure if I can pull it off. I have done a switch mod for my megadrive 1 and it works perfectly.

heres the mod http://www-unix.ecs.umass.edu/~dhowland/mod/

If I do this mod will it stop the sync issues with cheap LCD tv's and is it worth it?

[moonmaster1]

It would be worth it for the sharper image output.

I have had problems with s-video though and if you have a problem where s-video shorts out on your tv from time to time, i would just get av cables instead.

[jaxmazon]

It would be worth it for the sharper image output.

I have had problems with s-video though and if you have a problem where s-video shorts out on your tv from time to time, i would just get av cables instead.

oh okay well I might try and do it because I would like to have the best image possible for my megadrive but I heard that you can get the megadrive to run componet

[villahed94]

NOOOOOOOOOO
DON´T try that mod, use jamma-x nation one, it is easier and delivers an even better image. Just google it.

[jaxmazon]

NOOOOOOOOOO
DON´T try that mod, use jamma-x nation one, it is easier and delivers an even better image. Just google it.

you mean this one http://www.jamma-nation-x.com/jammax/genesismods.html its not very useful since it doesn't have much information about building the s-video mod I have to amit it looks much better but it explains more about making a megadrive 1 and sega cd 2 run from one psu than the s-video mod or is this the wrong mod?

[villahed94]

No,it's right just read it let me remember it in 2 hours(i'm at school)

[jaxmazon]

No,it's right just read it let me remember it in 2 hours(i'm at school)

okay thanks

[villahed94]

OK, I´ve returned
The following parts you need:
1 NTE85 or similar NPN general purpose transistor
1 220 uF Electrolytic or tantalum capacitor
1 0.25 W 27 ohm resistor
1 0.25 W 75 ohm resistor.
(the resistor values can be changed at desired, i used a 56 ohm instead of the 75 )

For Luma amp:


This means that the pin 16 signal must go on the right leg, the center one, must go on a +5 v source(you can use the Voltage regulators on it) and then in the left leg, you should put the resistor and after that you have a useful signal for Luma (use a PCB mountable S-Video Female Connector) .

For chroma is easier :
Take the signal from the pin 15 and connect it to the NEGATIVE side of the cap, then put the 75 ohm resistor and there you go, another useful signal.

For grounding, connect the 2 pins from the S-Video female to any metal part, like the screws on the voltage regulators or the RF Shield.

A useful pinout.

Well, that´s all. Don´t forget to add a rep!(click on the scale)

[jaxmazon]

OK, I´ve returned
The following parts you need:
1 NTE85 or similar NPN general purpose transistor
1 220 uF Electrolytic or tantalum capacitor
1 0.25 W 27 ohm resistor
1 0.25 W 75 ohm resistor.
(the resistor values can be changed at desired, i used a 56 ohm instead of the 75 )

For Luma amp:


This means that the pin 16 signal must go on the right leg, the center one, must go on a +5 v source(you can use the Voltage regulators on it) and then in the left leg, you should put the resistor and after that you have a useful signal for Luma (use a PCB mountable S-Video Female Connector) .

For chroma is easier :
Take the signal from the pin 15 and connect it to the NEGATIVE side of the cap, then put the 75 ohm resistor and there you go, another useful signal.

For grounding, connect the 2 pins from the S-Video female to any metal part, like the screws on the voltage regulators or the RF Shield.

A useful pinout.

Well, that´s all. Don´t forget to add a rep!(click on the scale)

Thanks for the help villahed94 I gave u some rep btw can I use these transistors http://cgi.ebay.co.uk/12-x-2N3904-NP...item439f86c870 for some reason I can't seem to find the NTE85 transistors and also will this make my megadrive 1 output stereo sound?

[villahed94]

Nope the stereo sound can be obtained from the headphone jack, use a generic jack to RCA cable, it would work. And 2N3904 is perfect, it is the one I used, so you can use it.


Woohoo I´ve done 250 posts so going to.....
WCPO Agent! Thanks to all guys at Sega 16 who has made me to encourage and get this!

[jaxmazon]

dam it I can't seem to find the CXA1145 chip on my motherboard I have a PAL megadrive does this mean I can't do the S-video mod?

[KillerBean2]

You need to remove the voltage regulator cooling plate in order to get to it.



But you say you have a PAL Megadrive. Do you live in Europe or do you live in the US? If you live in Europe, why don't you just use a SCART RGB cable? It's the best there is.

[villahed94]

Yeah, remove the plate, but you can do the mod, no matter the region of the system

[jaxmazon]

I have removed the heatsink and its not there its only a very small chip theres only a smaller chip and the reason I don't want to use RGB is because I want to get the best quality picture possible.

[KillerBean2]

and the reason I don't want to use RGB is because I want to get the best quality picture possible.

But RGB IS the best quality picture possible!

http://nfggames.com/atarilabs/meat/2...eoprimer.shtml