Famicom AV mod assistance

Hi all,

I tried to follow the guide here for the AV mod but unfortunately my FC is a 1989 HVC-CPU-GPM-02 model, so I do not have a resistor #12 and my board layout is different. I found this one and followed it instead: http://jpx72web.blogspot.sk/2016/11/famicom-av-mod-new.html

Unfortunately I am getting a garbled screen with no identifying pixel patterns that I can tell. It's definitely turning on, but it's just a mess. I haven't figured out how to hook up the audio yet because I didn't know if I could use the existing RCA jack for audio, so I don't know if there's any sound.

I did not have the exact resistor and capacitor values but used close ones (the 150R I used a 200, the 100R I used a 120; the 33uF capacitor I used a 47uF). I'm not sure if this is the problem. I lifted the pin that it mentions (rather than cutting traces).

I've attached photos of what I did here: https://imgur.com/a/zLVTX

This is the diagram that shows the gist of the mod: http://bit.ly/2osFPOn

 

I think trying with the correct value components should be your next step.
Here's how mine turned out:
http://8bitplus.co.uk/projects/famicom-av-mod-nintendo/

 

I'd also recommend ceramic caps under the board for the decoupling.

 

I will try that; parts ordered. Thanks!

 

I replaced all my substitutes with the correct parts and the aluminum capacitor with a ceramic one, and it's working now. Thanks!