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So I've been OCDing over this for the past month. So RGB to NTSC has good options still for a diy. What abut YPbPr (Component)? I've found a few circuits, one using a discontinued chip (The ROHM one). A circuit using two amps, but require -3.3v. Or using a bunch of transistors. Is there any good replacement for that rohm chip or an equivalent amp that just uses a standard 5v or 3.3v? I can probably find the ROHM encoder on ebay (I can), but would it be legit? Are there any ICs that do composite, svideo, and component? I've been wanting to mess around and make a DIY of that very spiffy JROK encoder, but I haven't figured out how he gets component.
 
does wiring RGB to VGA work on gonbes or ossc for both 31khz and 15khz?
I gave my Gonbes away (good riddance to bad rubbish) but yes if I remember correctly it WILL accept 15khz RGB via VGA port IF C-sync is wired to pin13 (normally H-sync in VGA head).As for the OSSC, no analog lowpass filters on VGA port... So even if it would accept 15khz that way (never tested it and never will) it would be inferior to SCART connector (which includes filtering).
Not trying to derail the OP topic even further but I'm curious of this part re: OSSC VGA port. If I want to connect a gscart switch to the OSSC for 15khz, you're saying that using the DB15 port would be inferior to the SCART port? Assuming this works re: c-sync wiring.

I don't have the gscart lite - just the regular gscart switch, so I get 1x SCART output and 1x DB15 output on my version. I'm looking to use them both simultaneously, one for analog display and the other for digital conversion via OSSC. I was hoping to use the DB15 port for the OSSC.
 
First things first, you MUST stop referring to the OSSC as having a "DB15" port, it's a high density "HD15" (aka a VGA) port (see the reference sheet below).
d-subminiature-tutorial-high-density.gif


I don't know how or why I keep having to go over this...
IF you are sending 31khz (with separate h/v syncs) video to the OSSC use the VGA port, if you are sending 15khz (with csync or sync-on-green) to the OSSC use the SCART port.
I'm looking to use them both simultaneously, one for analog display and the other for digital conversion via OSSC.
BUT what content (15khz/24khz/31khz) you are sending, has it got separate (h/v) syncs?
These are the only questions you should be asking yourself!

I would recommend you get a VGA-2-BNC cable and use the VGA out port of the gscart to feed an analog CRT/PVM/BVM, then use a direct wire scart-2-scart cable to connect the OSSC (provided the gscart's SCART output is wired for EURO standard, NOT JP21).
E-VGAF-5BNCM.png


This cable has 5 BNC leads because it's connected to both HD15 pin#13 (h-sync in a 31khz signal) and pin#14 (v-sync in a 31khz signal)...
If you are sending 15khz video you'll only use the lead connected to pin#13 (composite sync).
 
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Thanks. Much appreciated for the reply. I'm mixing up my terminology and it's good to know what all of this really means.
 
Not trying to be nit-picky... But when I see DB15 I instantly think supergun/AES controls, not VGA connector. :P
stick%20NEO.JPG


Truth is calling it a VGA connector (like everyone myself included always does) isn't accurate either, VGA refers to the format not the connector type.
The DB connectors using a high density pin configuration are referred to HD's.
 
Not trying to be nit-picky... But when I see DB15 I instantly think supergun/AES controls, not VGA connector. :P

Truth is calling it a VGA connector (like everyone myself included always does) isn't accurate either, VGA refers to the format not the connector type.
The DB connectors using a high density pin configuration are referred to HD's.
Let's get nit-picky: even "DB15" is not proper terminology for what people use on supergun controller ports (yes, I realize I'm guilty of calling them DB15).
220px-DSubminiatures.svg.png

DX-YY, where "D" is the shell shape, X is the shell size, and YY is pin qty. Many companies (myself included) have just given into the misnomers thrown around and advertise various D-Sub connectors as DB-whatever.
-ud
 
Do I need to convert anything if I just want to output RGBS (4x RCA, but SCART compatible) from Jamma to regular (European) CRT TV sets? I've read conflicting reports on whether you should use a Sync cleaner or not.

I also see lots of RGB adjustment knobs on several Superguns, are these primarily for boards with YPbPr or are they valueable to a RGBS build as well?

Also kind of related, what should I use to make sure the amped Jamma audio doesn't kill regular speakers?
 
Do I need to convert anything if I just want to output RGBS (4x RCA, but SCART compatible) from Jamma to regular (European) CRT TV sets? I've read conflicting reports on whether you should use a Sync cleaner or not.
You shouldn't need one.

I also see lots of RGB adjustment knobs on several Superguns, are these primarily for boards with YPbPr or are they valueable to a RGBS build as well?
You need to pull down the voltages on the RGB lines, so either resistors or pots.

Also kind of related, what should I use to make sure the amped Jamma audio doesn't kill regular speakers?
As long as the resistance you're putting on the audio line is 8 ohms or more, you're fine. So two 4 ohm speakers wired in series is OK. If you want to wire audio to a separate amp you need a line level converter.
 
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