GUIDE: AV mod your Famicom

Discussion in 'Modding and Hacking - Consoles and Electronics' started by Da Bear, Dec 20, 2013.

  1. Da Bear

    Da Bear Active Member

    Joined:
    Feb 2, 2012
    Messages:
    33
    Likes Received:
    0
    I thought I'll give back something to this community so today I have taken pictures of how I do AV mod to the old Famicom, replacing RF with composite and adding a RCA connector for sound. Minimal case modifying so it looks nice and almost original.
    Please note, my way is not perfect considering jailbars. Every Famicom is different, some are nearly perfect while others have visible jailbars.

    Here I cover the older version - HVC-CPU-0X. There is minor differences in the RF boards between revisions, but nothing that requires pictures of every one.

    Tools required:
    Philips screwdriver
    Soldering iron
    Solder sucker
    Wire cutter
    Round file
    (Dremel)

    Parts required:
    1x 200R Resistor
    1x 120R Resistor
    1x 220uF Capacitor
    1x 47uF Capacitor
    1x Red or White RCA connector
    ~8-10cm wire

    Unscrew the 6 screws and remove the bottom of your Famicom.
    Remove the screws holding the motherboard. If needed - disconnect the controllers.

    Top side of motherboard: Locate resistors R6 and R12 near the PPU.
    [​IMG]

    Remove both and replace R6 with the 200R resistor. Solder and cut the legs - save one.
    Jumper R12 with the leg you didn't throw away ;)
    [​IMG]

    Bottom side of motherboard: Solder the 47uF capacitor between PPU pin #22 (+) and #20 (-).
    [​IMG]

    Next we are going to modify the RF board and use it to route composite video to the RF connector.
    Desolder the marked spots in the picture. I use a fine tip and push the legs through the hole. Also remove the CH1/CH2 switch to make room for the audio RCA connector.
    [​IMG]
    [​IMG]

    Then solder the 120R resistor and the 200uF capacitor like in the picture. Make sure the old components you desoldered is not stuck in any hole.
    [​IMG]

    Unscrew the RF board and clean up. Cut the legs of the new resistor and capacitor.

    Now we need to remove some metal to make room for the RCA connector. I use a Dremel for this, but a round file for metal should work to.
    [​IMG]

    When you are happy with the metal work, solder the wire to the RCA connector and tighten it hard to the RF shield. Tip: I use 2 washers that are slightly bigger the the RCA connector to make it sit nice and firm.
    [​IMG]

    Solder the wire to cartridge connector pin #46.
    [​IMG]

    The final step is to make room in the case for the RCA connector. Here I use a round file for wood and carefully remove material next to the "RF switch". I regularly try to fit the RF board and remove more material if needed.
    When it looks good, I tighten RF board and then begin to remove some plastic from the bottom cover. Be careful, it's very easy to remove to much. Better take a little at a time and make sure it looks good.
    [​IMG]
    [​IMG]

    Refit the bottom cover and your Famicom should look something like this.
    [​IMG]

    Hook it up to your TV and enjoy.
     
  2. Mechagouki

    Mechagouki Site Supporter 2013,2014,2015

    Joined:
    Aug 18, 2013
    Messages:
    353
    Likes Received:
    12
    All tutorials should be this clear! Excellent, time to pick up a cheap Famicom I think.
     
  3. silverfox0786

    silverfox0786 Gutsy Member

    Joined:
    Nov 3, 2013
    Messages:
    432
    Likes Received:
    1
    is this only mono sound ?
     
  4. Da Bear

    Da Bear Active Member

    Joined:
    Feb 2, 2012
    Messages:
    33
    Likes Received:
    0
    Yes, only mono sound from Famicom and NES.
    You can make it "pseudo-stereo" if you want but that involves some more work. This just covers the basic AV mod.
    Or you could split the signal from the audio RCA connector if 2 audio cables are important to you with this thing.
    [​IMG]
     
  5. dc16

    dc16 Dauntless Member

    Joined:
    Jan 20, 2013
    Messages:
    751
    Likes Received:
    20
    This looks like the mod I would do if that RF jack is just an RCA jack. Does this use the same circuit that's commonly used meaning that the original rf signal actually went straight to the jack in the back?
     
  6. gladders

    gladders Robust Member

    Joined:
    Nov 1, 2013
    Messages:
    255
    Likes Received:
    15
    Probably a stupid question, but is it possible to RGB-mod a Famicom?
     
  7. Helder

    Helder Site Supporter 2014,2015

    Joined:
    Apr 6, 2013
    Messages:
    974
    Likes Received:
    51
    Good luck with that! I've been looking for one myself and they're expensive.
     
  8. ApolloBoy

    ApolloBoy Gutsy Member

    Joined:
    Sep 22, 2011
    Messages:
    425
    Likes Received:
    0
    Well yes since it uses the same hardware as the NES, but it's fairly challenging considering the amount of space you have to work with inside.

    They come around fairly cheap on eBay, you just have to look around. Sometimes they'll be advertised as "junk" when they really just need minor repairs, so that's something else to look for as well.
     
    Last edited: Mar 30, 2014
  9. Pikkon

    Pikkon "Moving in Stereo"

    Joined:
    Mar 4, 2005
    Messages:
    2,649
    Likes Received:
    48
  10. dc16

    dc16 Dauntless Member

    Joined:
    Jan 20, 2013
    Messages:
    751
    Likes Received:
    20
    Just don't get outbid by shill bidders. They are the worst. At work somebody bought a pretty expensive video game item but the buyer was 0 feedback in Brazil, so it's obviously a fake. eBay does little to protect either side from scammers, usually siding with a buyer. Best you can do as a seller is put some restrictions like "must have Paypal," and as a buyer wait for a second chance offer.

    Anyway, I hope Nintendium is as true as they say.

    How would one use this circuit:
    [​IMG]
    in regards to where the jumper is? I plan on using the circuit but don't really plan on drilling two holes into the system if that above method is cleaner. Or do I just cut some trace that connects to the jack closer to the end.
     
    Last edited: Mar 30, 2014
  11. Pikkon

    Pikkon "Moving in Stereo"

    Joined:
    Mar 4, 2005
    Messages:
    2,649
    Likes Received:
    48
    I would use this since this is what the av famicom uses.

    kyuusaku_zps6a57f5ab.gif
     
  12. dc16

    dc16 Dauntless Member

    Joined:
    Jan 20, 2013
    Messages:
    751
    Likes Received:
    20
    But I want to connect any of those circuits TO that port in the back with little mess as the guide above demonstrates so I can use that port instead of drilling an extra hole.

    And another thought. I'm very tempted in cutting the Famicom controllers and crimping into a RJ45 ethernet cable with coupler rather than buying actual NeoGeo extension cables. That way I can pick up some cheap SNES/NES extension cables and use my American controllers. Have other people done that? Besides if I want to continue using the original controllers I'd pick up a few extra cables and couplers.
     
  13. RetroSwim

    RetroSwim <B>Site Supporter 2013</B><BR><B>Site Supporter 20

    Joined:
    Dec 10, 2012
    Messages:
    603
    Likes Received:
    26
    There are two ways to do this.

    The old, inferior way is to find a replacement PPU from a Nintendo PlayChoice arcade board, install that in your NES/Famicom, and extract RGB from the appropriate pins. Some of the colours are off, and some games have visual bugs.

    The new awesome way is to buy a NESRGB board from viletim.
     
  14. gladders

    gladders Robust Member

    Joined:
    Nov 1, 2013
    Messages:
    255
    Likes Received:
    15
    Cool, does the NESRGB board emulate the NES or is it essentially the same thing, like, would some games be incompatible with it?
     
  15. RetroSwim

    RetroSwim <B>Site Supporter 2013</B><BR><B>Site Supporter 20

    Joined:
    Dec 10, 2012
    Messages:
    603
    Likes Received:
    26
    NESRGB isn't a clone system, it's a mod for real NES/Famicoms that sits in between the PPU and the mainboard, and creates an RGB signal.
     
  16. MangledLeg

    MangledLeg Peppy Member

    Joined:
    Jul 11, 2010
    Messages:
    340
    Likes Received:
    1
    It's also the most delicious a stock Fami or NES will look from what I've seen. I'm planning on adding one to my Twin and NES, but need the monies :)
     
  17. relo999

    relo999 Robust Member

    Joined:
    Jan 29, 2012
    Messages:
    233
    Likes Received:
    0
    I like to cut out the RF plug and place a stereo jack input instead, that way you dont have to mod the shell and it still looks like its supposed to with a stereojack to RCA plugs.
     
  18. Comboy

    Comboy Spirited Member

    Joined:
    Mar 8, 2014
    Messages:
    146
    Likes Received:
    64
    I just wanna drop you a line and say thank you. I just used this method on my Famicom and it worked on the very first try. This is my first mod and I definitely did not have all the right equipment. I was pretty seriously delayed from finishing up the final plug on the back while I waited for some parts that got lost in the mail. However tonight I finally got it all finished and put back together and I got a gray screen on the first try. I cleaned the game and system and bam, perfect screen. Except the jailbars..but you did mention that could happen.

    Anyways, thanks again!! Excellent, clean method and beginner friendly.
     
    Last edited: Jul 23, 2014
  19. Blashyrkhmr101

    Blashyrkhmr101 <B>Site Supporter 2014</B>

    Joined:
    Sep 10, 2013
    Messages:
    174
    Likes Received:
    11
    I was getting some audio buzz in my AV modded Famicom, so I put in an 220uF electrolytic capacitor like so:

    [​IMG]

    [​IMG]

    Great tutorial "Da Bear"!
     
    Last edited: Jul 23, 2014
  20. Segata Sanshiro

    Segata Sanshiro speedlolita

    Joined:
    Aug 5, 2009
    Messages:
    1,278
    Likes Received:
    11
    Nice to see some worthwhile soldering on a tutorial for once.
     

Share This Page