SNES mini/SFC jr RGB mod resistors

[hakujin]

According to http://gamesx.com/wiki/doku.php?id=av:snes2rgb you should use between 75 and 125 ohm resistors. Most guides I see seem to go with the 75 ohm value as the de-facto standard, but the image at the bottom of the page lists using 100 ohm resistors instead. I also came across this post: http://benheck.com/forums/viewtopic.php?f=3&t=40424 where a guy says 75 is far too bright and he preferred 130. Anyone tried different values? Is 75 too bright, or just right?

[Ed Oscuro]

Compare with this thread:
http://shmups.system11.org/viewtopic.php?f=6&t=45301

Looks like you might need to experiment a little.

[hakujin]

I completed the mod today and tried 75ohm resistors. The rgb output of my mini is significantly brighter than my old SNES. Everything looks amazing but I had to turn down the contrast on my BVM-20E1U to match the brightness of other inputs which is a hassle. If someone finds this thread in the future I'd probably go with 100ohms if I had to do it over.

[RGB32E]

I completed the mod today and tried 75ohm resistors. The rgb output of my mini is significantly brighter than my old SNES. Everything looks amazing but I had to turn down the contrast on my BVM-20E1U to match the brightness of other inputs which is a hassle. If someone finds this thread in the future I'd probably go with 100ohms if I had to do it over.

I've found the same to be true. A modded mini - 75 ohm resistors from R/G/B outputs on the RGB encoder are on the bright side. Adding a 68pF to 120pF cap to ground after the 75 ohm resistor helps filter out some high frequencies and seems to reduce brightness slightly. Stock SNES systems are generally darker like you mention. 1CHIP* revisions are slightly brighter than prior revisions. I've found it's better to have too bright than not bright enough output, as it's easier to tone down than it is to tone up.

I did not use the built in RGB encoder to tap RGB for the last SNES mini I RGB modded. I tapped RGBS directly from the PPU and buffered it with a THS7374. Turned out pretty well, but the picture was slightly too sharp. Might be good for a CRT though.


1CHIP-01 on the left, THS mini on the right.

[hakujin]

I actually took your advice from another thread and installed 3 mini ferrite beads inline with the resistors. I see no noise at all on my CRT but I don't have something like an xrgb mini to test on a plasma/lcd.