Technical and Repair Assistance

[amurphy245]

I really could do with some advice im running out of ideas.

By the way i live in the UK.

Alright i bought a famicom with the standard RF out,i then discovered that it probably wasnt going to work through rf because of the whole ntsc/pal thing,so i ordered a famicom that has already been modded with av outputs.

Now i cant get this one to work either,i can get sound but no picture whatsoever,ive tried it on 3 tvs and my monitor with no luck.

I took it apart and cant see anything wrong with it,no broken solder joints,caps are ok,no connections touching.It looks like the mod was done a long time ago but everything seems fine.

Im at a loss i dont know if the video is broken or its another tv issue but i have other jap systems that work fine on my tv.

[ericj]

First, check the 60-pin slot to see if 5V is going to it. If not, check the voltage regulator. If that's okay, check the fuse on the power board. If there's no continuity through it, bypass it by soldering in a small wire.

EDIT: Sorry, mis-read it the first time. I thought you didn't have sound. Good luck!

[amurphy245]

First, check the 60-pin slot to see if 5V is going to it. If not, check the voltage regulator. If that's okay, check the fuse on the power board. If there's no continuity through it, bypass it by soldering in a small wire.

Are you replying to my message? well i have sound so i know its playing the game fine i just got no video

[133MHz]

Check continuity across the video cable with a multimeter. If it's old, it could be frayed or broken internally.

[amurphy245]

Check continuity across the video cable with a multimeter. If it's old, it could be frayed or broken internally.

You mean the actual cable? well it has 3 cables (yellow,red,white) ive tried all 3 with no luck.

Are you sure their is no issue with it being a uk tv or something?

[133MHz]

You should at least get some sort of rolling, black & white picture or a very dim, distorted picture.
I mean that the yellow cable could be open or shorted internally, especially at the ends that it flexes the most. If you don't have a multimeter, try tapping video directly from the motherboard by touching the appropriate solder point with the tip of an RCA cable plugged into the video input of your TV, with the audio cable from the Famicom plugged in into that same TV to provide proper ground reference (since we already know that the audio works). This should rule out the cable itself as a culprit.

[amurphy245]

You should at least get some sort of rolling, black & white picture or a very dim, distorted picture.
I mean that the yellow cable could be open or shorted internally, especially at the ends that it flexes the most. If you don't have a multimeter, try tapping video directly from the motherboard by touching the appropriate solder point with the tip of an RCA cable plugged into the video input of your TV, with the audio cable from the Famicom plugged in into that same TV to provide proper ground reference (since we already know that the audio works). This should rule out the cable itself as a culprit.

Thanks dude,you know what it was after all that? the dam cables lol,after touching the motherboard with the cable and getting nothing i realized it has to be the cables so tried some different ones and worked perfectly.

Ive never known rca cables to be 100% dead especially all 3,one with giving audio but when i tried that in the video it was dead.

Thanks again

[ericj]

Correct. By the way, the Famicom uses a completely different way of interfacing four players. The NES Four Score multiplexes all the controllers' data into one port (or two?), while the Famicom's EXT port contains provisions for reading two extra controllers directly. Japanese Famicom games will try to read the controllers directly from the expansion port, while American NES games will look for a Four Score adapter and try to communicate with it instead, so you have to make up your mind on what kind of compatibility do you want to accomplish.

From what I read, I think the best way to go about this for 4-player functionality is to let the ground, latch, & +5v lines hooked up to the original spots on the PCB, wire up D3 & D4 to controller ports 2-4 directly, and wire the Clock and Data lines up directly to each port and cut the PCB traces.

The Four Score has an internal chip that all lines run through (don't have it on me now to take a look what it is exactly), do you think it will still work okay with the Clock & Data lines bypassing it? I assume the turbo function won't work this way.

Also, do you think I can let the Data & Clock lines run through the chip, but just cut the traces on ports 3 & 4 and piggyback them off ports 1 & 2?

[133MHz]

Also, do you think I can let the Data & Clock lines run through the chip, but just cut the traces on ports 3 & 4 and piggyback them off ports 1 & 2?

Not a good idea. The Four Score IC responds with a unique digital signature when probed by the system, leaving it connected will mess up things for ya.

You can leave it powered up if you wish, but don't connect any of the data lines to it.

[empo]

I just took apart my FDS that didn't load games and found a replacement belt made from electrical tape

Are the ones from tototek good?

[MrSoreto]

Hi everyone, I just recently found out about this forum while searching for a famicom AV mod guide. (and I must say, I really like the theme and layout!)
Yet I can not find it in the workshop section. I found a guide on another site in japanese, but that's for a diffirent model than my (1989) famicom. Is there anyone here that knows a guide for this particular model?

Much obliged!

[b1aCkDeA7h]

I just took apart my FDS that didn't load games and found a replacement belt made from electrical tape

Are the ones from tototek good?

I actually fixed two of them with $0.50 washers from Ace Hardware.

A friend of mine won this:

http://cgi.ebay.com/AV-Famicom-Controllers-Hookups-3-Games-glitchy_W0QQitemZ150431682568QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item23066d5008

Hasn't come in yet, but what would be people's preliminary diagnosis?

On another note, I now have a spare copy of Akumajo Densetsu to sell soon.

[UglyJoe]

If I plug a power strip into my step down transformer (120v to 100v), would all of the ports on the power strip effectively be 100v or does it not work that way?

[133MHz]

Exactly as you said.

[Jedi Master Baiter]

Exactly as you said.

would all of the ports on the power strip effectively be 100v or does it not work that way?

He said two things, which is it?