Can someone help me out with this AV mod?

[soop]

Hi guys, first post.  If everyone tells me to start again from scracth, then I'm going to have to, but it would be nice if I could just tweak what I've done to get it working.

The problem is, I found an instructional video and bought the parts to follow, but then opened my board to find a different revision.  I then did a google image search and tried to hack it to fit.

So what I bought for this video http://www.youtube.com/watch?v=FwKXFeKimGE was 2 22k resistors, a 47mf capacitor and a transistor (can't remember the type but it was originally for a PC Engine mod, and I read it would work ok).

But instead of looking like this: http://img6.imageshack.us/img6/4608/dsc09821b.jpg

It looked like this (this is actually my board) https://lh5.googleusercontent.com/-TKxh7Bm38Qo/T01AzYaqzDI/AAAAAAAAAw4/utjRZHL7au4/h301/2012-02-28

And So I tried to follow this as a guide: http://astrocadeage.com/famicom-bottom-board.jpg but moved the capacitor to the other end of the cable, negative end heading to the video out.

I've used a multimeter to confirm my soldering seems to be ok, but there's no vdeo, so I can only assume That I've soldered something to the wrong place, or the parts I've used don't work this way.

Any advice gratefully recieved.

[2A03]

Dump that mod and just use this instead. It's designed for an NES top loader but it will work with any Famicom. U5 is the PPU, U6 is the CPU.

[soop]

Ok, thanks, that does seem simpler.  Do you have a photo and any advice on lifting the pin?  I have a desoldering iron, but those are some chunky legs.

And is the transistor wired there facing it's flat face towards us?

[ericj]

I believe the emitter leg is the one on the left. That transistor should have a notch in the top of it.

[2A03]

I believe the emitter leg is the one on the left. That transistor should have a notch in the top of it.

Yep, the emitter is left, collector is center and the base is right.

[Hamburglar]

Dump that mod and just use this instead. It's designed for an NES top loader but it will work with any Famicom. U5 is the PPU, U6 is the CPU.

Hello, is this circuit better than the circuit in the AV Famicom?  I've tried many circuits and the AV Famicom circuit has always worked great for me no matter what model Famicom I use it on.

Curious, I want to try it and see for myself...thought I'd ask first. 

[Drakon]

try swapping the transistor pins.  Often I'll find multiple datasheets for the same transistor but the pinouts will differ.

[soop]

:O  Really? so swap the transistor around 180 degrees?

I can't believe they can differ the pinouts like that, I thought that was one of the things that can destroy it!

[Drakon]

:O  Really? so swap the transistor around 180 degrees?

I can't believe they can differ the pinouts like that, I thought that was one of the things that can destroy it!

it won't break the transistor at all.  I'm serious when I've looked up datasheet for transistors often I've found 2 datasheets for the exact same transistor with opposite pinouts.

[soop]

cool, I'll try that.  Thanks

[famifan]

yes, same transistors could have differents pinouts, it depends on the manufacturer.

always check datasheet for the manufacturer too to avoid this cace.

[2A03]

Hello, is this circuit better than the circuit in the AV Famicom?  I've tried many circuits and the AV Famicom circuit has always worked great for me no matter what model Famicom I use it on.

It's very similar to the AV Fami circuit, just that it uses a 75 ohm resistor on the emitter instead of a 100 ohm resistor. I actually didn't come up with that circuit, that was created by Longhorn Engineer.

[Drakon]

yes, same transistors could have differents pinouts, it depends on the manufacturer.

always check datasheet for the manufacturer too to avoid this cace.

If you're lucky enough to have the manufacturer actually written on the transistor.

[soop]

one more thing - what about the audio?  Just the same as my other diagram?

And should I bother with "stereo"?

[Drakon]

one more thing - what about the audio?  Just the same as my other diagram?

And should I bother with "stereo"?

I only found 1 audio circuit out there that sounds great and it comes on an expensive kit.  I wouldn't bother with the common stereo mod.