Universal RGB to Component Design

[SwampFox56]

Any NPN transistor will work but you need to see your transistor's data sheet to be sure what pin is what, I show something else on the schematic simply because of the foot print but I tend to use the 2N3904 for my projects including this one and if you want a similar project board ( I say similar because it lacks some of the extra resistors) I can provide a link to one I shared some time ago on Dirty PCBs.

PCB Manufacturers I've used many over the years and besides OSHPark there is

http://dirtypcbs.com/
http://smart-prototyping.com/PCB-Prototyping.html
http://www.dfrobot.com/index.php?rou...y&path=135_134
https://www.itead.cc/open-pcb/pcb-prototyping.html
http://www.hackvana.com/store/

I've used all of these above except smart-prototyping but they should be good as well.

PCB Link:
http://dirtypcbs.com/view.php?share=1778&accesskey=

I also use tayda for many parts and they deliver within the week since they have USA distributors.

I totally missed this. Excellent information Helder! I very much appreciate it and I'm sure many others will to!

[SwampFox56]

I thought I'd ask since I'm copying your schematic - what is the value of the diode? And are you using non-polar caps?

EDIT: I answered my own question a couple posts back... I feel like a dumbass.

[Helder]

The original post has the original schematic with polarized electrolytic caps. On my final design I used ceramic smd caps, either or will work.

[SwampFox56]

I went ahead and made of copy of Helders Genesis board. It's kindof a hybrid between SMD and through-hole. Some components are purposely overlapping a bit (like the 2N3904's overlapping the SMD resistors). Untested as of now. Waiting for the PCB's to show up. But in case anyone else was curios... here you go.

[Helder]

Nice! And I see you removed that extra cap like I said but know that you might have to use a 500 ohm pot on 160 ohm resistor if the video is jumpy and adjust that as needed then get the pot value for use with an actual resistor. Be sure the resistors are 1% or colors might be a little off.

[SwampFox56]

Nice! And I see you removed that extra cap like I said but know that you might have to use a 500 ohm pot on 160 ohm resistor if the video is jumpy and adjust that as needed then get the pot value for use with an actual resistor. Be sure the resistors are 1% or colors might be a little off.

Huh, I'll put that in my Rev 2.0 board. Btw, I was trying to find the trimmer you used in your original board (the thesteve's schematic) but I can't find it in the Eagle library. Can you give me the library with that trimmer (and the trimmer part number in Eagle)?

[Helder]

The Eagle Library was a custom made part but I have no reason to not share it so here ya go.
http://www.mediafire.com/view/m42t5r...uHole-Pots.lbr

and the actual pot:
http://www.taydaelectronics.com/pote...istor-6mm.html


You don't need to add that there in your design but it's helpful, I was merely stating that you should use a pot like it to adjust the picture sync if it's needed then use a multimeter to get the value that it's stable at and use the closest resistor value to it to use in place of the 160 ohm.

[SwampFox56]

The Eagle Library was a custom made part but I have no reason to not share it so here ya go.
http://www.mediafire.com/view/m42t5r...uHole-Pots.lbr

and the actual pot:
http://www.taydaelectronics.com/pote...istor-6mm.html


You don't need to add that there in your design but it's helpful, I was merely stating that you should use a pot like it to adjust the picture sync if it's needed then use a multimeter to get the value that it's stable at and use the closest resistor value to it to use in place of the 160 ohm.

Excellent thanks for sharing That'll be very useful since I always order from Tayda. Anyways - if this prototype works out working well, I'll offer YPbPr modding on the Genesis... I'll see if I can tweak it for other RGB supporting consoles as well. I'll probably add in the pot simply because every system is different and using a timmer to adjust the sync on a per-console basis would probably be best...

[SwampFox56]

Board came back from fabrication... and I underestimated the form-factor of the caps... alot. Soldering job is kind of messing, though that's largely that's due to the fact that I'm using a Hakko-shit clone soldering iron since my Hakko-888 iron (station is fine) is no longer working.




Anyways, board updated to 1.1B

[Helder]

Haha I made a similar mistake long ago on such a board, but yea if your caps are smaller in diameter than the transistors then you will likely have an issue. Simple fix is to use 10v or 6.3v caps since they are usually much smaller in diameter.

[SwampFox56]

So I've been playing around with the circuit you posted on DirtyPCB. So far it looks really good, but by adjusting the pots, I either get too much red bleeding over, or too much green bleed. I read the entireity of the thread and I noticed that you mentioned changing the resistors after the caps to 2K, and adding resistors before the caps.

Are the resistor before the cap values the same as your Genesis PCB? Anything else I should note? Thanks Helder

[Helder]

The Genesis had too much green bleeding so it was best to add 1k or 2k pots right where the inputs go before the input caps. Set them to zeroand adjust as needed, my newer board I made for my own testing purposes has all this on it so I could test each console and have a dedicated board for each system.

[SwampFox56]

The Genesis had too much green bleeding so it was best to add 1k or 2k pots right where the inputs go before the input caps. Set them to zeroand adjust as needed, my newer board I made for my own testing purposes has all this on it so I could test each console and have a dedicated board for each system.

Thanks for the tip. Kinda wish you said that before I ordered the protopack from dirtyPCB :/ Ah well. I currently have my own board that I plan on getting fabricated. I'm curious, in your personal design, do you use 1K or 2K pots before the caps?

As little testing as I need to duplicate your results would be a time saver (not to mention a money saver) and I'd greatly appreciate any info

I don't plan on making my board public. I'd like to keep this proprietary (which I don't feel bad about since there isn't ANYONE online who has ever shared a perfect RGB to Component converter).

Guess I could breadboard designs, but ever since taught myself how to use Eagle, I've become "addicted" to designing my own PCB's :P

[Helder]

Well apparently other people used a similar design and all say it works good in PCE and some other systems but on the Genesis that green killed it for me so no idea how truthful people were in those statements.

Here is the board I made with clear as day values, Also ditch those through hole transistors as you can get hundreds of smd transistors for literally pennies and they ake up less space on the board:

[wolf]

Well apparently other people used a similar design and all say it works good in PCE and some other systems but on the Genesis that green killed it for me so no idea how truthful people were in those statements.

Here is the board I made with clear as day values, Also ditch those through hole transistors as you can get hundreds of smd transistors for literally pennies and they ake up less space on the board:

Helder, you are the BOMB!!! I was looking endlessly online on how to do a mod for RGB to come out of my US Model 1 Sega Genesis. But I do need some assistance, I have little experience with soldering. The things I did was basically learning off YouTube. So the first thing that I did as a first timer I was able to bring back my not working sega genesis back to life when I discovered that I had to create a bridge in the power supply board because the board itself was bad. So that was my first and it was a success! The second was me creating an s-video out with 3 rca out (includes stereo from the headphones location). That part was a success too. Also I have no idea why I bothered with the 3RC but I did it anyways mainly because I can but s-video mod beats it all the way easy.

So that's pretty much experience so far and I am learning. But with this mod, I do need help with getting/purchasing the parts for this mod. Because I have seen on another website that sells something called RGB jailbar amp. So I don't know which option would be best and simple to do without harming the console. I would also need to know how to solder which wire goes to where on the sega genesis board. I saw your diagram on the first page of this thread and I'll be honest, I have trouble understand/reading that schematic diagram. >_< But if you can guide me I'm sure I'll be able to do it. I would really really appreciate it. =D