Video issue with a Taiwanese Famicom

[HVC-001]

Hello dear famicom lovers,
I just got my hand on a Taiwanese version Famicom but I'm having trouble with the video output.
The system is modified with an AV cable and has a frequency switch in the back. I do not know if the AV mod is original or not though.

I own 3 tv sets, one is an LCD I bought in Hong Kong, the other 2 are CRT from France with NTSC support. All of my japanese or asian systems work fine on any of them, even my 2 AV Hong Kong version Famicom. But that Taiwanese console shows me either a screwed-up-diagonal-flickering black & white screen (on crts) or a screen with a very bad vertical hold problem (on lcd).

My questions are, do you think Taiwan got a strange NTSC format somehow ? Do you think that Famicom AV is faulty ?    could it be something else ? 

[famifan]

ugly AV mod is responsible for that, i think

any videos/pics?

[HVC-001]

I will try to take some pictures tonight and post them  
Post Merge: September 05, 2012, 10:35:34 am
Hi here's a picture I have on one of my CRT tv set.

Now the one with V-hold probem on my Hong Kong LCD (notice how the colors are a bit screwed up as well).


What appears to be strange is that sort of screw seal at the back of the system, like it's never been modified or something (unless the modder did put that sticker back in the day).


Would opening the console be of any help solving the problem ? I can try to find some time next week end to do so and take pictures if it helps.

[famifan]

video output impedance should be 75 Ohm
/thread

[P]

What appears to be strange is that sort of screw seal at the back of the system, like it's never been modified or something (unless the modder did put that sticker back in the day).

My guess is that the sticker is something the original AV modder put on before selling it, not Nintendo.

[HVC-001]

@famifan > I'm sorry if I'm asking a silly question, I'm quite new to the famicom mod scene, but what does that mean ? (*gonna hit the search button I think...)

@P > it's quite hard to say, even though I think you're quite right here, but with those asian versions it's so hard to say. For exemple with my Hong Kong Famicom, how to differentiate an AV mod that's been made by Simon & Toys or by a third party ? And maybe Simon & Toys modded these Famicom,, or at least some of them, to Hong Kong standard through a third party... *sigh

Anyhoo, I just hope you can help me fix this problem...   I find this taiwan version quite cool but it would be even more if it could be used to play with, that's for sure hehe.

EDIT :
Here's some pictures of the motherboard if it can help, hell that baby was dirty...

[famifan]

@famifan > I'm sorry if I'm asking a silly question, I'm quite new to the famicom mod scene, but what does that mean ? (*gonna hit the search button I think...)

no problem. Choose any video amplifier circuit from this thread http://www.famicomworld.com/forum/index.php?topic=8080.0

additionaly you have a chance to remove annoying jailbars  

[80sFREAK]

I can see guts, but i can not see the mod

[133MHz]

Funny, I can see it just fine.

[80sFREAK]

Do you call it "mod"?