RGB quality black japanese PCE Duo

[Moosmann]

Today, I modified 2 PCE for RGB, all with the same amplifier.
The quality from the small white PCE is great, but on a black japanese Duo (CD-Rom & HU in one) i get a very bad quality (shadows on right side).

I have this bad quality with each amplifier in all resistors/condensator combinations, or just the transistor the same result.

http://markus.brandel.bei.t-online.de/DUO-rgbscreenshot1.JPG
http://markus.brandel.bei.t-online.de/DUO-rgbscreenshot2.JPG

Particularly the color white looks worst.

Do have every black DUOs bad rgb ?

Bye Markus

[davidleeroth]

I have similar problem with a N64 RGB mod. It worked with the old amp but using the new PC-E amp (transistor BC33725) brought the problems.  

[Moosmann]

Which transistor do you have in the old amp ? And which circuit (resistors, condensator) ?

I never had a problem with a BC33725 in a US N64.

Bye Markus

[davidleeroth]

I used the "old and crappy" PC-E amp:



I took composite/RGB comparison photos of N64 when I made the old amp, take a look. I understand that the old amp wasn't good but the results were IMO. I just wanted to know if the picture could get even better.

[NFG]

From what I've been told the amp shown above is a crappy amp that delivers good results for this purpose.  I've never built it and have no opinion.