Consolized MVS 1C system RGB output problem

bovined

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Hello all, been a longtime lurker and appreciate all the great info here. I have a consolized MV1C system that I bought as is from someone a year ago and it was modded for S-Video. The S-Video works fine but when I tried to use the standard AV out port with the proper RGB output cable I cant seem to get it to sync properly with my Sony BVM/PVM monitors. The strange thing is that I can get a proper output through a Frameister by setting the sync level from 0 to 30 (not even sure what that does.) Does anyone know the issue here and how to go about getting a fix for a good RGB output signal?

thanks!
 

ChuChu Flamingo

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Do your monitors expect TTL level sync or 75 Ohm?

From what i've seen framemeisters usually aren't as picky but you gotta be careful with what sync you send to it. The good thing is that it works on your framemeister so it definitely points to a sync problem imo. Just a word of caution Ste from hdretrovision has pointed out that although you can get away with not using 75 ohm sync for most shit, it is certainly pushing the framemeister past the manufacturers recommended tolerances if you don't attenuate them to 75 ohms according to the datasheet.

In any case is your sync line on the mvs board attenuated for 75 ohm via resistors? What RGB cable are you using specifically for the MVS system & output? Does that cable have any resistors?

If possible try to take some pictures of your setup,mod, and what cables you have (where you got them as well). Im just shooting basic information until someone more knowledgeable chimes in. Best of luck.
 
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bovined

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Thanks for the info ChuChu! yeah unfortunately I am not sure as I bought this consolized MVS second hand. I will open it up and try to determine that or get some pics.

For the RGB cable itself I tried this one: https://goo.gl/n8iBSP

but I think I need one of these specific to MVS systems: https://goo.gl/FzmJci

but to be honest I am pretty confused about which one I need now...
 

ChuChu Flamingo

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That seller is most likely using pin 7 for sync which is why he says some aes consoles will have csync, others will have composite. What this tells me about the cable is that it probably doesn't have resistors to bring down csync to 75ohms. Not sure if the diagram is wrong below as almost every picture I came across is broken due to photobucket being gay.

pinout.jpg

I wouldn't bother with the second cable as it uses sync on luma and is for the Omega CMVS. Unless you have a omega cmvs or the person who modded it has the same pinout on the din connector you will have compatibility problems (mainly it won't sync due to no luma).

Atleast it works on your framemeister so we know it has to be a cable issue imo.

-Have you tried any other consoles on your pvm/bvm through rgb?

-What breakout cable are you using to connect directly to the pvm?

-What model pvm/bvm?

On a unrelated note for anyone reading this wall of text, what happens if you send a ttl signal straight from a console to a sync stripper? Would it still be syncing? Maybe that is your problem.

But yeah if you have a multimeter and want to see if your cable is attenuated or not here is a good video.

https://www.youtube.com/watch?v=Z3sE3uk5kPU
 
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Dark Sakul

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I been asking the same questions elsewhere in the greater retro gaming community. Though to look here and found this thread.

I don't think a multimeter is the right tool for the job, the problem, being a multi meter measures constant current and a C Sync is a signal, a wave form. So with a Multimeter you will get a fluctuating reading.
I know for Sega Genesis RGB Scart cables there a 470Ω resistor to bring down the voltage level and a 10µF capacitor for DC coupling. So I decide to replicate that for my MVS dedicated Super-gun (so almost a Consolized MVS).



Here is the attenuation circuits I made for myself, I got the specs from bits and pieces I found elsewhere. I am not sure if the Sync circuitry is correct or not, but its what I have in my current setup.
By the way I have a MVS MV1T board, the board it self has no modifications other than original battery replaced for a 2032 battery holder mod (with the resistor for recharging removed) and a Unibios.
21766510_10214195409180867_5136947906733518326_n.jpg
The RGB Lines has a 75Ω resistor and a 220 µF cap (blue), the Sync is a 470Ω resistor and a 10µF cap (Brown) .
 

ChuChu Flamingo

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When I said to use a multimeter, it was just to see what components are in your cable. To make sure you have 75ohms you really need an oscilloscope and to display a true pure white screen with the console powered on to see if it is 75 ohms or not iirc.

TL;DR basically you need to make sure your system output is in spec with the input of whatever device you use (75 ohm for consumer equipment generally, TTL for various other things). Some devices can operate on either.

Pretty cool stuff there you built. Whenever I see someone consolize a board they usually wire it to a Jrok/Neobitz or some other type of encoder that handles the proper attenuation to 75ohms. Xian Xi would definitely be the person to ask what you need to have on your RGB lines since he does a lot of consolizations. What type of video display are you using for that MV1T?
 
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Dark Sakul

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When I said to use a multimeter, it was just to see what components are in your cable. To make sure you have 75ohms you really need an oscilloscope and to display a true pure white screen with the console powered on to see if it is 75 ohms or not iirc.

TL;DR basically you need to make sure your system output is in spec with the input of whatever device you use (75 ohm for consumer equipment generally, TTL for various other things). Some devices can operate on either.

Pretty cool stuff there you built. Whenever I see someone consolize a supergun they usually wire it to a Jrok/Neobitz or some other type of encoder that handles the proper attenuation to 75ohms. Xian Xi would definitely be the person to ask what you need to have on your RGB lines since he does a lot of consolizations. What type of video display are you using for that MV1T?

As of right now it's going to a XRGB 2 Plus to a Older HD TV with VGA Input. Although I am waiting on a OSSC to be shipped next month.
 

bovined

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That seller is most likely using pin 7 for sync which is why he says some aes consoles will have csync, others will have composite. What this tells me about the cable is that it probably doesn't have resistors to bring down csync to 75ohms. Not sure if the diagram is wrong below as almost every picture I came across is broken due to photobucket being gay.

View attachment 46557

I wouldn't bother with the second cable as it uses sync on luma and is for the Omega CMVS. Unless you have a omega cmvs or the person who modded it has the same pinout on the din connector you will have compatibility problems (mainly it won't sync due to no luma).

Atleast it works on your framemeister so we know it has to be a cable issue imo.

-Have you tried any other consoles on your pvm/bvm through rgb?

-What breakout cable are you using to connect directly to the pvm?

-What model pvm/bvm?

On a unrelated note for anyone reading this wall of text, what happens if you send a ttl signal straight from a console to a sync stripper? Would it still be syncing? Maybe that is your problem.

But yeah if you have a multimeter and want to see if your cable is attenuated or not here is a good video.

https://www.youtube.com/watch?v=Z3sE3uk5kPU


Sorry to revive an older thread but I just got around to wanting to fix this issue for REAL now and appreciate your assistance folks especially ChuChu.

To answer your quetions:

-Have you tried any other consoles on your pvm/bvm through rgb?
ALL my other consoles work fine using their supported RGB cables to the Sony PVM/BVM breakout cable to the BVM as well as through my Frameister

-What breakout cable are you using to connect directly to the pvm?
this one from WookieWin https://goo.gl/pNpmnQ

-What model pvm/bvm?
This is going to my Sony BVM D20F1U

I got a hold of a multimeter and checked the sync line on pin 7 both with the NeoGeo RGB cable and the WookieWin breakout cable and BOTH show .000 so I assume that means there are no resistors or caps is on those lines? So are you saying that the connection from the sync line through the breakout to the BVM needs to read 75 Ohms?

The other reason I am trying to fix this now is that I obtained the K2_Video NGPC board and it ALSO seems to have the same issues in that I have an improperly synced signal to the BVM but cannot get it to show on the FM no matter what I set the sync level to.

the K2 is connected with the same wookiewin breakout from the unit and then using a male to make generic scart cable to the other wookiewin breakout on the BVM and I get these results:

https://imgur.com/a/vjzryej

if I enable ext sync from the BVM it seems to get worse.
 
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bovined

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Could this just be a case where I need a sync stripper? Does the MVS C1 normally sent sync across the composite signal? Would a sync strike work to resolve these sync issues?
 

Neo Alec

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The MVS doesn't have a composite signal. It's an arcade board, so it has R,G,B and TTL sync.
 

Neo Alec

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I would add the cap and 470 ohm resistor to the sync line. Standard AES cables won't have enough resistance built in.
 

bovined

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I would add the cap and 470 ohm resistor to the sync line. Standard AES cables won't have enough resistance built in.


Oh I see, you are suggesting to do what Dark Sakul did to his sync line in his post above right? I will hunt down those parts and give it a shot.
 

Xian Xi

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Depending on the MV1C, some rarely need a sync cleaner. If it's via BVM, make sure your BVM isn't the SOG(Sync on Green) type. Also, press EXT Sync.
 

bovined

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Depending on the MV1C, some rarely need a sync cleaner. If it's via BVM, make sure your BVM isn't the SOG(Sync on Green) type. Also, press EXT Sync.

thanks Xian. The BVM is def not sync on Green as my other consoles are working fine and do not support RGsB. When I hit the EXT sync button it just gives me a different type of interference that is even worse that without ext sync disabled. Both are unplayable.
 

Xian Xi

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thanks Xian. The BVM is def not sync on Green as my other consoles are working fine and do not support RGsB. When I hit the EXT sync button it just gives me a different type of interference that is even worse that without ext sync disabled. Both are unplayable.

How is your RGB connected to the BVM, SCART to BNC? Snap a pic of the interference, that would help me judge what it's from, hell video even better.
 

bovined

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How is your RGB connected to the BVM, SCART to BNC? Snap a pic of the interference, that would help me judge what it's from, hell video even better.

Here is a video of the K2_video sync issue:

https://www.youtube.com/watch?v=fyJuJKrhCY8

I have the K2_video hooked up with the wookiewin RGBS BNC to female Scart -->standard male scart to make scart cable --> another wookiewin female SCART to RGBS to BVM.
 
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Finch

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Here is a video of the K2_video sync issue:

https://www.youtube.com/watch?v=fyJuJKrhCY8

I have the K2_video hooked up with the wookiewin RGBS BNC to female Scart -->standard male scart to make scart cable --> another wookiewin female SCART to RGBS to BVM.

Holy hell dude you know you can get cheap RCA cables from amazon. Do what I do, buy a component video cable for $4.99 and buy a RCA composite video+audio cable for another $4.99 and then just use the Composite video line for sync. It's what I do, and it's sure easier to deal with than like 5 different SCART cables chained together. You might even have enough of these lying around your house already.

If your BVM has BNC connectors for the RGB I highly recommend a pack of BNC to RCA adapters, makes this stuff WAY easier.
 
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bovined

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Holy hell dude you know you can get cheap RCA cables from amazon. Do what I do, buy a component video cable for $4.99 and buy a RCA composite video+audio cable for another $4.99 and then just use the Composite video line for sync. It's what I do, and it's sure easier to deal with than like 5 different SCART cables chained together. You might even have enough of these lying around your house already.

If your BVM has BNC connectors for the RGB I highly recommend a pack of BNC to RCA adapters, makes this stuff WAY easier.

Thanks Finch. I do have the BNC to RCA adapters for component hookups and didnt even think to try those yet. Let me hook it up that way to isolate and minimize the crap in between and see what happens.

This would still leave me with the issue in that the device is not working with either of the SCART RGB upscalers which I still believe could be sync related but this will def help isolate one way or the other.
 
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Finch

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Yeah, sorry if I sounded harsh. Not bagging on your for using SCART, but that many cables going one to another feels like something else could be going wrong somewhere in there and you'd never know it. It's also nice with RCA cables as you can unplug them one at a time to kind of troubleshoot what it and isn't working. Plus, chances are everyone has enough of them in a drawer somewhere to do a full RGBS+LR even if the colors don't all match up correctly.

I made a little converter box that changes SCART to RCA cables and vice versa for testing purposes, although I don't use a OSSC or framemeister or anything so SCART isn't really too important to me at the moment, but I plan to get one in the future so I wanted to be SCART ready.
 

bovined

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Yeah, sorry if I sounded harsh. Not bagging on your for using SCART, but that many cables going one to another feels like something else could be going wrong somewhere in there and you'd never know it. It's also nice with RCA cables as you can unplug them one at a time to kind of troubleshoot what it and isn't working. Plus, chances are everyone has enough of them in a drawer somewhere to do a full RGBS+LR even if the colors don't all match up correctly.

I made a little converter box that changes SCART to RCA cables and vice versa for testing purposes, although I don't use a OSSC or framemeister or anything so SCART isn't really too important to me at the moment, but I plan to get one in the future so I wanted to be SCART ready.

lol dont worry about it man...I was looking at it myself after a few mins and thinking wtf as well. Process of elimination is def the best way to go from here to try and figure out where the issue is. I use SCART for everything else in the chain of my devices to display to upscaler etc but this is the first device that had BNCs OUT for the video signal so in my head i keep wanting to end up at a SCART connection.
 

bovined

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Thanks again for the recommendation Finch! I bypassed the scart cables and adapters and just used BNC to RCA connectors on both sides and simply plugged in the 4 video signals direct with RCA cables and it is now working fine to my P/BVMs! I went to the CRTs direct with my CMVS 1C and it also is working now so there must be something along the cables that is messing up the sync.

MY question now is how I can send that clean signal to either the Frameister or OSSC now?

Would it be easier to try and send the RGB + sync to the upscalers or modify the existing SCART cables to deal with the issue? I could also output the signal from the BVM back out via scart but will probably run into the same issue as far as I understand what I am seeing here.

EDIT: I guess I just need this? https://retro-access.com/products/8-pin-mini-din-nes-rgb-to-extron-bnc-phoenix-pro-coaxial-multicore
 
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Neo Alec

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If I had a PVM I would just use scart to BNC.

I would focus on your scart cable.
 

bovined

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Thanks for all the help and suggestions everyone. I ended up buying the following cable to go direct from the K2 to the frameister: https://retro-access.com/collection...for-extron-to-xrgb-mini-pro-coaxial-multicore and it works perfectly fine. I am no closer to understanding WHY but I am sure its the info everyone was trying to relay in here about getting TTL level sync to the FM. Now to figure how to wire everything up so I dont have to have direct connections for everything to work properly!
 
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