Supergun RGBS video out (to Sony PVM) issue

[Aleanil]

I recently picked up a Sony PVM-1353MD, a 13" 15khz RGB monitor. Tested it with a PS2, and sure enough it handles 15khz beautifully. So! I decided to round up my box of parts and actually put together a supergun (mostly in anticipation of gunbird18's shmupmeet in a couple weeks).

The problem I've run into is that I'm not getting video out successfully. The PVM-1353MD is based on the 1350 chassis (meant for medical uses for microscopes and such) and has 4x BNC for RGB input - R(ed), G(reen), B(lue), and External Sync.

No problem, I figured - I took two old BNC cables, chopped them in half, soldered them to a DB9 and put the RGBS from the jamma connector to a DB9. I tied Red to the Red cable, Blue to the Blue cable, Green to the Green cable, and Sync to the External Sync cable, and tied the grounds of all four cables to the video ground off of the jamma loom.

Problem is, the supergun works fine when the cable is unplugged. Game boots, I hear audio, etc. But when I plug in my oh-so-wonderful video cable, nada. The monitor goes loopy and the board goes quiet. If I unplug the cable, then the board reboots and is fine.

I've checked my wiring three times over, and I haven't found any crossed wires or bridged gaps. Anyone have a clue what could cause this? Or perhaps my method of tying all the grounds together won't work? I haven't found much info on people taking jamma to BNC, so any info or advice would be appreciated!

[antron]

what you did with the grounds should be fine. when you checked for shorts, did you use a multimeter?

[Aleanil]

Yeah, I used a multimeter to check for continuity between the jamma connector and the end BNC cable. First runthrough with the multimeter I actually found that my DB15 female/female adapter was busted and had to replace it. After that, all good.

[antron]

Yeah, I used a multimeter to check for continuity between the jamma connector and the end BNC cable. First runthrough with the multimeter I actually found that my DB15 female/female adapter was busted and had to replace it. After that, all good.

and you checked for shorts between all colors and ground?

[Aleanil]

Yup. =/ That was my first thought too; didn't know of anything else that would cause it to shut off in that fashion besides something being grounded that shouldn't be grounded.

[antron]

is there a 75Ohm temination button on that monitor?

edit: manual says it's auto.

how did you connect the PS2?

is the monitor set to RGB?

you may have to go into the menu to enable the external sync as well.

[Aleanil]

No button for it, but the manual stated that it has built-in termination. I tested in both inputs (both are 4xBNC; no nice, simple, 9-pin or 15-pin or 25-pin ones - just bog standard BNC).

Incidentally, I just ripped out the video ground wire and the thing boots and I get audio; all I see on the monitor is a white screen with three fuzzy pink lines on it, but it boots. Think I need to find another 15khz capable device around and test my cables there to see if it's the supergun or the monitor. I noted that when I test my PS2, it only works under component - the RGB out from PS2 to the RGB in on the monitor no workie; it never syncs correctly and all I get is a rolling screen. I almost wonder if the monitor actually supports RGB in the way it says. But it's a Sony PVM, so it *should*...

[antron]

you have to set it to RGB in the on-sceeen menu (according to the manual I found on the web)

[Aleanil]

In the on-screen menu, it has:

RGB - Internal Sync
RGB - External Sync
Component - Internal Sync
Component - External Sync

Alas, none of the options give me anything more than rolling static. The PS2 uses Component - Internal (because it uses RGB only, no external Sync, as it does Sync on Green). As I understand, jamma RGBS should be RGB External Sync for this monitor. Should.

Thanks for your help so far though, it's appreciated to have someone else to help me think through things and point out what I'm missing.

Edit: I'd say it could be the PCB I'm using (Kageki), but it's my universal test board and it works fine in my cab.

[antron]

PS2 is only sync on green for 480p and higher
try the PS2 with RGB internal, and set it to RGB on the PS2 as well.

wait, are you using PS2 component cables? you need 4 lines for RGB (and the PS2 doesn't do c-sync)

[Aleanil]

PS2 is only sync on green for 480p and higher
try the PS2 with RGB internal, and set it to RGB on the PS2 as well.

wait, are you using PS2 component cables? you need 4 lines for RGB (and the PS2 doesn't do c-sync)

Oh! That'd be the problem, I am using plain old component cables for my PS2.

Well, shoot... I think I'm going to yank the VGA->BNC cable from my PGM-2950 and put the RGBS from the jamma board to a HD15 connector to connect to that VGA cable. Then I won't be dealing with my own crappy soldered cables, just a soldered connector. Maybe that'll help.

[antron]

there are two set of BNC jacks right? one set is output, right?

[Aleanil]

Ha!



Thanks for your help, Antron! The issue turned out to be the BNC cables I laboriously soldered to a DB9. Heck if I know what was wrong, but when I used a real manufactured VGA->BNC cable and just took the jamma output to a HD15 connector, it seems to work. Now I just need to wire up controller inputs and this supergun will be complete. (And a bit of tidying up wires and bundling them too; it's messy right now).

Thanks again!

[nem]

Nice! I have the exact same monitor (got it from a hospital that were throwing out their old equipment)