SG-1000 Composite or S-Video Mod?

[ultramecha]

Does anyone have instructions on how to mod a SG-1000 for composite or even s-video? I would be super grateful for any information on how I can mod my system (Its not a MK II just the original SG-1000)

[phoenixdownita]

Does anyone have instructions on how to mod a SG-1000 for composite or even s-video? I would be super grateful for any information on how I can mod my system (Its not a MK II just the original SG-1000)

 

For the first model it seems it has a TMS9918:

http://park21.wakwak.com/~suka/sega/ippatu/sg1000/hontai/hontai.html

 

which emits composite already on pin36

http://www.smspower.org/uploads/Development/TMS9918.pdf

[you may need to amplify/buffer it, technically you could drop in a replacement 9928 which has R-Y,Y, B-Y instead (Y = luma for SVideo) but then you would have to find an appropriate encoder which may be a pain just to get SVideo, alternatively you may be able to drop in the F18A FPGA replacement board, check the ti99 forum for more details, it's not the cheaper solution, I'd try pin36 first]

 

For the SG-1000II you can bring out RGBS as they used a proprietary Sega component that already generates them for you:

http://www.nightfallcrew.com/02/09/2012/rgb-synch-amplifier-circuit-for-sega-sg-1000-ii-mark-2/

 

Finally you may be better off asking those questions on smspower.org forums.

[ultramecha]

 

For the first model it seems it has a TMS9918:

http://park21.wakwak.com/~suka/sega/ippatu/sg1000/hontai/hontai.html

 

which emits composite already on pin36

http://www.smspower.org/uploads/Development/TMS9918.pdf

[you may need to amplify/buffer it, technically you could drop in a replacement 9928 which has R-Y,Y, B-Y instead (Y = luma for SVideo) but then you would have to find an appropriate encoder which may be a pain just to get SVideo, alternatively you may be bale to drop in the F18A FPGA replacement board, check the ti99 forum for more details, it's not the cheaper solution, I'd try pin36 first]

 

For the SG-1000II you can bring out RGBS as they used a proprietary Sega component that already generates them for you:

http://www.nightfallcrew.com/02/09/2012/rgb-synch-amplifier-circuit-for-sega-sg-1000-ii-mark-2/

 

Finally you may be better off asking those questions on smspower.org forums.

 

Thank you so much for the reply! I found the pin out for the sound chip https://en.wikipedia.org/wiki/Texas_Instruments_SN76489. Does Pin 7 look like the correct pin for sound out?

Also I wanted to ask if there are some good instructions on how to build a simple composite out amp/buffer, (Provided that I need one of course). And Last question, a stupid one, but can I solider the ground wire to pretty much any metal point? Trying to find a good place to get ground from without hopefully frying the board.