PC Engine RGB jailbars, let us find a working solution

[kamiboy]

Putting additional bypass caps on each of the 6280's vcc pins usually removes any jailbars. Doesn't hurt to put a single 220uF on one of them either.

Why is this necessary though? Is there noise in the 5v current being supplied by the regulator?

[Artemio]

I just made release 1.0 of the 240p suite for the PC Engine, CD-ROM2 and Super CD-ROM2: http://shmups.system11.org/viewtopic.ph ... 9#p1064949

I did't add anything in particular to check for the banding, but it has the usual RGB full screen color selection test, as well as the rest from the regular suite. Let me know if you have any suggestions for this particular issue.

The Soldier Blade color that makes them most visible to me is 0,1,1 in the RGB test.

[kamiboy]

Success!

Long story short, I soldered SMD 47uF caps next to the already present SMD caps on C131, 134, 135, 136 and the banding is no longer visible on the B&O. These are the modifications from the Otaku store, only he suggested 100uF caps, which I did not have at hand, so I used 47uF and it worked out regardless.

In short, the Otaku store mod works, DO IT!

[speedlolita]

I installed no additional caps and don't have banding.

[keropi]

Success!

Long story short, I soldered SMD 47uF caps next to the already present SMD caps on C131, 134, 135, 136 and the banding is no longer visible on the B&O. These are the modifications from the Otaku store, only he suggested 100uF caps, which I did not have at hand, so I used 47uF and it worked out regardless.

In short, the Otaku store mod works, DO IT!

did you use ceramic or electrolytic caps?

[kamiboy]

These are the tiny square SMD caps so they are not electrolytic, not sure what they are though.

[kamiboy]

I installed no additional caps and don't have banding.

Well, I needed them for my Core Grafx and B&O TV. Different hardware configurations change the outcome it seems.

[Voultar]

I'm curious to know how well a Duo-R does with the capacitors.

[keropi]

I search around otaku store and found this:

IMPROVEMENT: It is possible that light strips/bars appear on the image, (more visibles on light backgrounds). It doesn't come from the kit, but from the console. You can soften them by installing capacitors (you can buy them here):

so he is using electrolytic caps along the ceramic smd ones (makes more sense). The small ones are 100uf and the large one I have no idea. Maybe 1000-1500uf , next to filter the 7805 output?

[kamiboy]

I didnt bother replacing the cap next to the regulator.

I think it might be 470, 330 or 220uf. Doubt it is 1000uf though.

[kamiboy]

I didnt bother replacing the cap next to the regulator.

I think it might be 470, 330 or 220uf. Doubt it is 1000uf though.

As for the four 100uf caps, you will have to use SMD or flat capacitor for the Core Grafx as radials will not fit.

[Artemio]

I had already tried the Otaku store solution in my PCE Duo, and the banding still shows in some colors on my PVM 2530, for example RGB(0, 1, 1). I tried out 100uF, 330uF and 1000uF in parallel with C909, and today I added a .1uF for high frequency. It didn't help though.

The banding is really faint, and only visible in those darker colors.

[leonk]

Currently I have a TG16 and waiting for my rgb amp parts to come in including 9 pin mini din for Genesis 2 SCART cable usage. Currently I'm playing with RF hookup. I giggle when I read about the faint jail bars. You guys should hookup RF to get a new perspective.

[Artemio]

Currently I have a TG16 and waiting for my rgb amp parts to come in including 9 pin mini din for Genesis 2 SCART cable usage. Currently I'm playing with RF hookup. I giggle when I read about the faint jail bars. You guys should hookup RF to get a new perspective.

I also have a TG-16 modded for RGB, and that shows no banding at all in the exact same setup. I bet you'll enjoy it.

[kamiboy]

Looks like I am going to have to get me a OG PC Engine.

[Artemio]

I found something interesting today. I just got a white PC Engine with a IFU-30 and CD-ROM2 unit, I always wanted that model. I modded it for RGB, replacing the RF out with an 8 pin Mini Din from the PCE; since I wanted it to do RGB out even when stand alone - and that mod looks very clean aesthetically as well.

I used the THS7314 mod, from the EXT port. I tested out the PCE and it works really well, banding was not visible and levels were right. I then plugged it into the IFU-30 to try out some CD games and surprise: banding was very noticeable... and the video levels were higher. Everything was brighter.

Suspecting the IFU-30 does some amplification on the EXT port, I opened the PCE again and moved the RGB wires to the Huc6260 instead. And levels went back to normal, and banding was again non noticeable.

[kamiboy]

I actually have a IFU-30 that has been modded with an RGB out, so there is no need for modding the PC Engine hooked up to it.

It will be interesting to see what results I will get if I hook a white PC Engine to it.

[CkRtech]

Was doing a bit of reading today on the pcenginefx.com forums and saw a comment that user thesteve wrote concerning video output noise on a Turbo Duo -

to solve jail-bar issue on rgb modded system replace capacitor C961 10uf with 100uf tant or 220uf aluminum

Source: http://www.pcenginefx.com/forums/index. ... #msg204770

I am almost done capping my unmodded Japanese Turbo Duo with the caps provided by console5. I am going to leave it stock for now (calibrate the laser and get it back up and running), but I have made a note to replace that cap again with one meeting his suggestions when I eventually do the RGB mod.

Artemio: You mentioned the Otaku solution not working for you and your PCE Duo. Although I linked to that earlier, I haven't read the details. You mentioned C909 a few posts up. Perhaps thesteve's solution might help you out? It would be nice if it does. Admittedly, it would probably push the RGB mod to the Duo up higher on my console "to do list" as well.

[kamiboy]

Unfortunately I do not have any tant or alu caps, so I'll have to invest in them and try this trick with my Duo. As it stands it exhibits pretty clear jailbars, so improvements should be easy to detect.

[RGB32E]

Tim will soon be releasing a RGB amp that can be perfectly tailored for the PCE/TG16 systems. Without any "fixes" for jail bars it produces the cleanest RGB signal for these systems I've seen! Here's a teaser taken via XRGB-mini:

[rtw]

Tim will soon be releasing a RGB amp that can be perfectly tailored for the PCE/TG16 systems. Without any "fixes" for jail bars it

Which Tim is this ?

[RGB32E]

Which Tim is this ?

viletim

[CkRtech]

Good thing I held off, then. Where did he announce this?

[rtw]

Which Tim is this ?

viletim

Nice, got any links to actual hardware ?

[RGB32E]

Nope. Tim will post detailed info on the kit when he's ready.

[Fudoh]

excellent news! Do you know from which type of PCE the above snapshot was taken ? Duo, standalone, interface unit ?

[RGB32E]

excellent news! Do you know from which type of PCE the above snapshot was taken ? Duo, standalone, interface unit ?

I took the picture. It's in a booster. Other amps I've tried 2SC1815, NJM, THS (with or without AC biasing circuit) all had much worse JBs by comparison.

[CkRtech]

Nope. Tim will post detailed info on the kit when he's ready.

You tease!

[rtw]

I have an IFU-30A I am going to RGB mod, should I wait for Viletims solution or can I use the Otaku one ?

[Pasky]

Betting money it's just another one similar to these two:

http://www.db-elec.com/home/News/dbgraf ... perational:



http://www.neo-geo.com/forums/showthrea ... BoostMasta:



So probably no need to wait.