Using aluminum foil instead of copper foil for reducing jailbars on av famicom?

I have av modded my HVC-CPU-GPM-02 famicom successfully but with jailbars. I was just wondering if it's ok to use aluminum foil for shielding the PPU if I don't have the copper one.

 

try it
will be hard to solder too though

 

i just now finished this mod on a 02 with a lifted pin 21 and a warped and earthed the ppu with copper.
it only reduced the severity, not removed it completely.
So if you do try foil, dont get get dishearten because its just not a 100% fix.

I have also done this on the 07, the 07 has a better result but still not 100%

 

I will try tomorrow.

Yeah I know it will only reduce the bars.

 

ok, get rid of those ceramic caps if you used them

turns out if you use a 220uf 10v on the ppu with + to pin 22 - to pin 20 it is a 100% fix for me

if you have that cap handy, try that without the foil.

i started off using 220uf 25v but that didnt work as well as the 10v

works on the 07 too

 

I also noticed that sometimes, a large electrolytic can filter jailbar-type noise better than a couple SMD ceramics.
I don't understand why that is, but I've seen it in practice.
Could be a poor choice of SMD caps versus a nice E-cap.

 

I didn't have a 10v cap so before doing the foil method I tried a 50v 220uf instead and was surprised and happy with the result. Jailbars are almost gone.

I tested two famicoms. One is AV modded while the other one is untouched using the original rf switch that came with it. I tested the two on a 32 inch Haier LCD TV (cheap).

Here are pictures for comparisons:
1. Famicom 1 - AV modded using http://jpx72web.blogspot.sk/2016/11/famicom-av-mod-new.html but NO ppu shielding and NO 1uf ceramic caps on ppu.

Very noticeable jailbars.


2. Famicom 1 - AV modded using http://jpx72web.blogspot.sk/2016/11/famicom-av-mod-new.html with 220uf 50v cap on PPU but NO ppu shielding.

Very very light jailbars. Is this because of my LCD TV?


3. Famicom 2 - untouched using RF

On famicom 2, I'm not sure if this is normal with jailbars. Again, is it because of my LCD TV?

I will probably get an old CRT tv to test further.

 

( how satisfying is it getting rid of those jailbars? )
thats a pretty impressive result for not having any shielding, when i went from 25v to 10v there was a dramatic difference.

If you get a 10v and that it clears it up 100% that saves you a whole lot of trouble removing the ppu, even with my fakeko 808

its likely that using a crt will improve things but id still get a 10v for the sake of it

 

When I started modding mine I decided to remove the PPU just to test the cheap vacuum desoldering tool I bought on eBay China before using it on an old Macintosh 128k. It was a mess! It took me a lot of time to finally remove the PPU. I didn't have the 1uf ceramic caps and the copper shield so I came here asking if it's ok to use aluminum instead.

So yes I'm very satisfied and very happy. Thanks to you!

This famicom I'm talking about was actually PAL modified that's why I can't get it to work here in the Philippines. I read somewhere that AV modding might only be my option. So I av modded it.

I just noticed right now that the cap I soldered to PIN 46 for the sound is actually a 10v 220uf cap. So I will try to remove that for now and replace the 50v cap I used. Will update later...

 

Here are caps I tried:
1. 220uf 10v - pulled from a used cheap electronics parts
- slightly worse than the previous 50v 220uf cap (used, capxon brand,looks like quality cap)

2. I bought these 3 different caps earlier. These are all 220uf and new. No available 10v so I bought one 25v and two 16v different brands. All 3 caps seems to have the same results. They are only very slightly worse than the 50v capxon cap.

I'm eager to test it on a CRT TV but I've already sold my Sony Trinitron a long time ago. I hope to find one again.

By the way, the third picture above, is that normal for unmodded famicom on a newer LCD tv?

 

i haven't used RF since 1998 but you can expect it to be the worst signal possible

i dont know how my eyes handled the N64 with RF

 

We were young and dumb and not yet jaded by superior video signals!

 

When you av modded your famicom, did you lift pin 21 of the PPU?

 

yes i lifted the pin, makes a huge difference

 

Ok thanks.

Any particular brand you used for the 10v 220uf? Is it a HVC-CPU-GPM-02 too?

 

ive done it on a 02,06,07

they all seem to behave the same.

i use Nichicon, panasonic are good too

 

I found my cheap almost new 14 inch Changhong CRT TV and tested all the capacitors I mentioned above on my av famicom. I didn't notice any difference on the results as they are all clean without any jailbars. There are only very visible jailbars when no cap is connected between pin 20 and pin 22.

As for the unmodded famicom on this Changhong CRT TV using RF, I can see light jailbars which is much better than on my 32 inch LCD TV.

Is the pin20 & pin22 capacitor hack applicable on an unmodded famicom?

 

i dont know, i cant use the RF