CMVS Video encoder options...

goombakid

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I've been messing with my old 2 slot CMVS that I made several years ago. IIRC, the video encoder that I used was a Neobitz one. It was getting along with my Retrotink x2 and x5 just nicely until tonight while I was playing with my NeoSD . The RTx2 doesn't show video at all. To make sure that the x2 wasn't dead, I hooked it up to my LD, and that worked fine. It works ok with the x5, but then midway through a game, the game gets wonky and glitches out. Same thing happens when I play just a regular MVS game.

I'm gonna dig into it and maybe try to clean it out. However, are there any other newer solutions for an RGB to NTSC encoder for CMVS nowadays? Any suggestions? Thanks all!
 

daskrabs

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The AD723/4/5 series for composite/S-video. Not sure about something that does component.

Edit: I guess people use THS7374 for component. I'm not aware of an "all-in-one" chip that's currently being produced.

Edit2: For a full component encoder, see here for a schematic. Uses BA7230LS as well as THS7374. Not sure if both are needed as I've seen solutions that use just one or the other. The BA chip is out of production, but can still be had.
 
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Neo Alec

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Seems like we get this question from time to time, but there's very low demand for these these days (because most use digital TV's or analog RGB now), which is why they're no longer produced.

You're basically asking to be able to convert from RGB to composite/S-video to HDMI. There's no reason to have that many steps when you can just go from RGB to HDMI.
 

goombakid

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You're basically asking to be able to convert from RGB to composite/S-video to HDMI. There's no reason to have that many steps when you can just go from RGB to HDMI.
I figured that would be the way to go at this point. I'll have to mess with it later again with my x5 and an SG.
 

Neo Alec

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If you have a Retrotink 5X then RGB is the way to go. If you're not into soldering, unfortunately you'll probably need someone to wire it up.
 

goombakid

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If you have a Retrotink 5X then RGB is the way to go. If you're not into soldering, unfortunately you'll probably need someone to wire it up.
Is there anything specific that I have to do with sync (specific capacitor or resistor needed)? I'm all for soldering shit.
 

Neo Alec

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Is there anything specific that I have to do with sync (specific capacitor or resistor needed)? I'm all for soldering shit.
220uf caps on the RGB and sync lines. 470 ohm resistor on the sync line and 75 ohm resistors on the RGB lines (the resistance needed on the RGB lines varies).

Alternatively, you could buy a board like this one, which uses an encoder chip and has low pass filters for the video and audio:
 

Hawwa

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220uf caps on the RGB and sync lines. 470 ohm resistor on the sync line and 75 ohm resistors on the RGB lines (the resistance needed on the RGB lines varies).

Alternatively, you could buy a board like this one, which uses an encoder chip and has low pass filters for the video and audio:

¿These are the same values for consolizing a MVS and having it outputting RGB? I have one CMVS I made myself but only put pots on the RGB lines, no capacitors and nothing on the sync (two in the pink). I remember buying some caps because I saw a Xian Xi post stating the values for making this the proper way but now I can't find the caps or the fuckking post I saw...
 

Neo Alec

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You can get by without the caps, but it works better with them in my experience.

Since I tinker with consoles from time to time, I just bought variety kits full of caps and resistors off of Amazon or Ebay. They were cheap, and now I usually have what I need for any project.
 

Hawwa

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Ok, since I have to put the resistor on the sync line anyway I'll go ahead and add the caps. Because that is "mandatory", ain´'t it?
 
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