sega sg-1000 cvideo mod

http://www.youtube.com/watch?v=QBTEwwbUcjI

The sega sg-1000 doesn't have rgb capabilities ! The TMS9918A ic it uses has composite ,as it's best output ,there's no rgb available from it.I modded the one i had and the data sheet notes a 330 ohm pulldown resistor on the cvideo line ,which helps with sharpness of the video.A lower value resistor gives faster fall times ? and a sharper picture.

http://emu-docs.org/VDP TMS9918/Datasheets/TMS9918.pdf

http://en.wikipedia.org/wiki/Texas_Instruments_TMS9918#Specifications

 

Found a sega sg1000 for £100 near me in a shop is it worth that much boxed.

 

If it has the black stripe on the case front,then yes,quite a bloody bit ,the normal blue striped version is about that price.But if you look around the uk retro sites,they have one for £500