Hi guys,
First of all i would like to say i should have been on this forum way earlier but i guess i didnt realized the NES was so unique and well conceived for it's time. Nintendo truly did make miracles with this 8 Bit system.
Anywais with that said.. I'm currently in the process of refurbishing and re-capping NTSC front-loader NESes but in my testing i realized i had at least two different models and maybe even more different board revisions.
I did some testing with one unit which has an Alps RF modulator/power supply bloc and after hooking it up true componant on my LED TV i noticed evenly spaced "jailbars" from the pale colors. Mostly visible with pale blues sky some light brown and light green palettes.
I would take screen shots or/and captures of Super Mario Bros. to show what i mean if necessary but i want to know how this is possible on unmodded NES consoles. Video signal is too weak for all i know... I read alot about this issue but it seemed to be only present on some PAL top-loaders and mostly only appeared after RGB mods. I may be wrong buty i don't think i've come across lots of topics with unmodded Front-loader NES having jailbar problems.
I would also like to mention that i didnt see this issue on front-loader NES wich had a Mitsumi RF/power supply bloc but after hooking that same system two differents capture card (hauppauge PCI HVR-1600, and some Pinnacle 7$ clone i got from ebay; i have direct componant input on both of these cards) i get jailbars even worst on the clone that i cant get on my HDTV but on the hauppauge i seem to get a decent video output but with some faint diagonals lines :/.
All that said i need to do some more testing to sort all this out; i have taken the rf/power bloc and connect pin 21 from PPU to an small basic video amp circuit to see if i still get jailbars so on and so. I already mounted the PPU for the console i'm testing with on a 40 pin DIP socket and changed all electrolitics capacitors on the board with no really noticable differences with those jailbars.
In the end i will need find a solution to bring these consoles as new as possible with strong video out signal (without jailbars at all) but without adding componants or modifying the console other than maybe remove some unecessary componants to simplifying the video signal circuit. Those maybe will come later with as reburbished mod ready consoles or something on ebay (still don't know i got like 20 of them nad might get alot more in the future lol).
I'm still in the process of completing a little 5 volt test station to easily test the repair or modifications without soldering de-soldering 100 times the rf/power bloc but if i can get any pointers in this forum i will take any advices i can from experienced techs i will gladly take them.
Edit: All references to Componant video is of course wrong. I meant composite.
First of all i would like to say i should have been on this forum way earlier but i guess i didnt realized the NES was so unique and well conceived for it's time. Nintendo truly did make miracles with this 8 Bit system.
Anywais with that said.. I'm currently in the process of refurbishing and re-capping NTSC front-loader NESes but in my testing i realized i had at least two different models and maybe even more different board revisions.
I did some testing with one unit which has an Alps RF modulator/power supply bloc and after hooking it up true componant on my LED TV i noticed evenly spaced "jailbars" from the pale colors. Mostly visible with pale blues sky some light brown and light green palettes.
I would take screen shots or/and captures of Super Mario Bros. to show what i mean if necessary but i want to know how this is possible on unmodded NES consoles. Video signal is too weak for all i know... I read alot about this issue but it seemed to be only present on some PAL top-loaders and mostly only appeared after RGB mods. I may be wrong buty i don't think i've come across lots of topics with unmodded Front-loader NES having jailbar problems.
I would also like to mention that i didnt see this issue on front-loader NES wich had a Mitsumi RF/power supply bloc but after hooking that same system two differents capture card (hauppauge PCI HVR-1600, and some Pinnacle 7$ clone i got from ebay; i have direct componant input on both of these cards) i get jailbars even worst on the clone that i cant get on my HDTV but on the hauppauge i seem to get a decent video output but with some faint diagonals lines :/.
All that said i need to do some more testing to sort all this out; i have taken the rf/power bloc and connect pin 21 from PPU to an small basic video amp circuit to see if i still get jailbars so on and so. I already mounted the PPU for the console i'm testing with on a 40 pin DIP socket and changed all electrolitics capacitors on the board with no really noticable differences with those jailbars.
In the end i will need find a solution to bring these consoles as new as possible with strong video out signal (without jailbars at all) but without adding componants or modifying the console other than maybe remove some unecessary componants to simplifying the video signal circuit. Those maybe will come later with as reburbished mod ready consoles or something on ebay (still don't know i got like 20 of them nad might get alot more in the future lol).
I'm still in the process of completing a little 5 volt test station to easily test the repair or modifications without soldering de-soldering 100 times the rf/power bloc but if i can get any pointers in this forum i will take any advices i can from experienced techs i will gladly take them.
Edit: All references to Componant video is of course wrong. I meant composite.