1989 famicom with true rgb, s-video, redone sound amp, nes controller ports

This started out as a 50$ shipped ebay famicom. I added everything I'd ever want to this unit. Here's a quick schematic of how to wire nes controller ports into a famicom properly



Repeat for the player 2 connections just ignore the mic pin since nes controllers don't use it.

Here's some internal pictures, yes I use a lot of hot glue to keep things fastened I'm very efficient at removing hot glue if I ever need to change something:






Here's the demonstration video:



I managed to solve the jailbars in rgb (probably for all models of the nes / famicom). These upgrade kits I use have the rgb from the ppu go directly into a sony video encoder at point blank rnage. I tried having the rgb ppu sit in the regular ppu socket and I sent the rgb by wires to the kit at the back but that added distance between the ppu and the video encoder added jailbars. Having the rgb ppu sit in the kit and relocating the entire ppu socket removed the jailbars. The less distance between the rgb ppu and the video encoder / rgb amp the less jailbars I got.

This kit I upgraded the video encoder from the cxa1645 to a cxa2075 producing much sharper s-video with better looking colours. I also built a small circuit that divides the system master clock down so it's capable of driving the video encoder which removes the colour bleeding. This kit normally drives the video encoder using a crystal oscillator but since it's not on sync with the system master clock it adds colour bleeding which is why I built the clock divider circuit to fix that.

I swapped out the chip that allows the powerpak to work with a rgb ppu, thanks to acem77 for that discovery.

The rf box has been removed and stripped of the bare minimum parts to run the system. The power regulator circuit and heatsink are bolted at the front of the case to make room for the upgrade kit at the back.

I installed a switch that lets you real time switch the audio between the default circuit and the upgraded circuit I installed. The upgraded circuit balances the volume levels between the system audio and famicom carts with audio chips very well (much better than the default circuit). I also prefer the bass and treble levels of the upgraded circuit. This audio circuit has a pseudo stereo sound effect but I just set my amp to mono to remove that effect.

 

The only way to properly connect a NES controller to a Famicom is use the 15 pin connector on the front of the Famicom.

 

Some games don't work with an external controller though, SMB2/Super Mario USA being a prime example.

 

Yeah I've explored that idea a little before. Mounting NES controller ports on the Famicom would be hard to get looking right. The case just isn't built for it.

 

Is there not a circuit/chip that just offers Mono or is this the only one? NES/Famicom games were not designed for stereo and neither is the sound output from the chip so i've always reviled the idea of people trying to make NES stuff stereo. it just sounds awful. (not directed at you. People in general.)

Also: I have a toaster NES and i've never noticed any Jailbars on it through composite. Only on the top-loader and the toploader famicom. (then again I haven't really been looking hard either)

I wonder if there is a way to get RGB(and thus YPbPr through a transcoder or something) on a toaster.

 

Someone discovered that the jailbars come from the PPU data traces running under the GPU on the motherboard and had the bright idea of isolating it with grounded copper tape... Was that you, Drakon ?

 

any reason why not choose the av famicom(1993)?

i am too against stereo mods. Cleaner audio mods are always welcome though.

 

I like the A/V Famicom because it already has NES controller ports on it not to mention it looks a hell of a lot better than the original Famicom...

And I think if memory serves me correctly this Famicom/ NES is the best when it comes to clean RGB output from PC10 PPU mod.

 

It also has the multiav port - no need to make a hacked up connector or drill holes in the case.

 

For people who dislike fake stereo you can just set your amp to mono (that's what I do). Or just mix the two channels together using two 10k ohm resistors if you feel like it.

Yeah you can get rgb in any model. I've built by commission / for personal use rgb toasters, a rgb twin famicom, and more rgb av famicoms than I can remember. I still have a few commission av famicoms / rgb chips to build together sitting here.

No that wasn't me. Back when I started making these I made the jailbars a little better by using the video out ground pin on the ppu for video out only but it was far from perfect. Then I started using these japanese upgrade kits. Turns out these kits posess the solution to the jailbars and video sharpness by having the rgb fed into a video encoder / amp at point blank range. I've since installed a better video encoder in these kits, improved the video circuit, and recently removed the low pass filters from the audio circuit giving you a teeny bit more treble.

Also as you can see with this famicom I have all 40 ppu connections running unshielded underneath the entire pcb and still there's no jailbars on the screen. I'm not too sure about this shielded wire theory.

I just built this for fun. I have 2 personal av famicoms with all the same upgrades.

Yup. Also the audio circuit I'm using really is designed for the av famicom so it doesn't sound as perfect on other models. The av famicom is ideal there's more room under the hood, it has the multi av port, it has the audio wiring for famicom carts, really it's the easiest (and best looking) model to do this stuff to.

 

I am itching to try shielding the PPU on a standard NES and see if it makes the faint jailbars it has on composite disappear ...

 

How did you redo the sound amp? Op amp? What exactly makes it "upgraded"?

 

I didn't design the circuit it came with the japanese kit I use. It's a couple of opamps, a virtual ground, inductors on the outputs, and resistors / caps. Just recently I removed the low pass filter caps it sounds fine without them (probably a little better).