Famicom Composite Mod:
- Change R6 to 220 ohm (along edge of board)
- Change R12 to 100 ohm (along edge of board – this changes voltage divider to output a "stronger" video signal)
- On RF modulator, remove components to isolate CVBS, there are 2 or 3 components you need to remove, or you can cut traces.
- Install 100uf / 16v cap with positive side facing signal source (Famicom motherboard, this blocks the DC)
- Connect negative side of cap to RCA jack going to your monitor
- Try 102 tantalum cap (1nf) between video and ground at RCA jack to smooth video
- If you want to reuse the RF jack for video, you need to isolate it by removing a couple components. Then add a wire to connect it to the 100uf cap above.
Note: video will have jailbars, this is just how the video is on the earliest Famicom boards.
For Audio, you can take the audio right off the feed going to the RF modulator, but you should install something like a 10uf cap, with positive facing the Famicom motherboard to remove DC offset. You should remove components on the RF modulator to isolate the audio going into the RF modulator.
Note: Audio will be buzzy, with interference picked up from the Famicom main board.
— Links
Schematics all from NESdev and Console5 Wiki:
https://www.nesdev.org/wiki/File:Neswires.jpg
https://wiki.console5.com/wiki/Famicom
SMMC episode where I first showed the Original Famicom and AV Famicom:
Adrian’s Digital Basement ][ (Second Channel)
https://www.youtube.com/channel/UCbtwi4wK1YXd9AyV_4UcE6g
Support the channel on Patreon:
https://www.patreon.com/adriansdigitalbasement
My GitHub repository:
https://github.com/misterblack1?tab=repositories
— Instructional videos
My video on chip removal without damage:
— Music
Intro music and other tracks by:
Nathan Divino
@itsnathandivino
About The Author
