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Rikrok

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I have a House of the Dead (1) board and I'm trying to get it all hooked up. I asked last week in the worrying bomb thread but no luck, I'm hoping someone will see it here. Since then I've spoken to someone who knows more about electronics than me but I'm still in the dark. I have a tri sync monitor which can handle the 25kHz, but I'm very worried about just plugging it in and damaging either my monitor or board.

Here are the input specs of the monitor:

Input Signals
• Video Input connector 1:15 pin D-sub high density male; VGA
compatible Analog .7 to 1volt level with 75 Ohm input.
• Video Input connector 2: 10 pin connector Analog 2.2 to 4 volt
level at 250/350 Ohm; CGA/EGA 0.156 center header.
• Sync type: TTL & Standard CGA / EGA / VGA/ sync (positive or
negative).
• Sync input: Separate or composite sync from 1 volt to 5 volt input.
• Sync Input Impedance: 2.2K Ohm (H sync and V sync)
• Horiz. / Vert. sync frequency: 15.75 to 40 KHz / 40 to 100 Hz.

Attached you can see that TTL input which can take up to 4V. I measured the voltage between R and ground coming from the board and it gives me 4.9V. I was worried about that but the person I was speaking to said that's with no load, it will drop when it has one. So the voltage seems ok, that leaves me with the Ohms question...

The specs say it should have 250/350 Ohms, how do I know if that matches what my Model 2 gives?
 

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I took the gamble, made a cable and plugged it in to the monitor. Nothing went up in smoke but the screen kept displaying "no input detected" (other than a flicker when I powered up THOTD). I guess it's not surprising as when I looked at the sync signal with an oscilloscope it just showed a constant voltage, no signal.

When I turn it on there are 8 LEDs next to each other that light up momentarily, then the 4 red ones on the right are lit, then just one up from bottom right stays lit. There's a green one bottom left which seems to vary in brightness. I can't find anything in the manual that say what these mean.

Can anyone shed some light on what I haven't done correctly? Should CN3 and CN4 on the little board (third picture bottom right) be connected to anything?
 

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Hey @Rikrok, did you ever get this worked out? I have a HOTD 1 with the same issue.
Unfortunately not, though its slightly reassuring to know I'm not the only one. I've just moved country and all my stuff won't arrive for another few months but once it does I've another Model 2 on its way to me (Virtua Cop 2). I'll see if I can get that working fine and hopefully it'll help shed some light on what's going on.
 
The TTL here looks like a Molex Series KK 10 pin. I should know because I recently built one of these for a CGA to VGA adapter (not converter) for my Model2b, which uses the same filter board:

E-KaCOHVgAk1-HA.jpeg


I could probably build you one of these cables if you wanted at whatever length you specify unless you think you could do it yourself.

EDIT: Ah, you've got a special cable with a ferrite ring I see. I can't see what's at the end of your cable, but you could always chop off whatever connector you have and add these pins into the housing I linked in the same configuration I've got in my example and you should be golden.
 
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The TTL here looks like a Molex Series KK 10 pin. I should know because I recently built one of these for a CGA to VGA adapter (not converter) for my Model2b, which uses the same filter board:


I could probably build you one of these cables if you wanted at whatever length you specify unless you think you could do it yourself.

EDIT: Ah, you've got a special cable with a ferrite ring I see. I can't see what's at the end of your cable, but you could always chop off whatever connector you have and add these pins into the housing I linked in the same configuration I've got in my example and you should be golden.
Thanks for your reply. The connector/cable hasn't been the problem for me, I made the cable with the right connectors to feed it to my monitor. The thing is I don't get any image. When I look at the R, G and B lines with a voltmeter they all measure a steady 4.9V and the sync is a constant 1.5V, so there's no signal.

Out of interest on your picture- are you using variable resistors to take the ~5V down to a vga friendly 0.7V?
 
Out of interest on your picture- are you using variable resistors to take the ~5V down to a vga friendly 0.7V?

I use this Mikesarcade adapter and feed the VGA to an Extron DVS 304 or an Extron RGB-HDMI 300 A scaler, which I'm assuming does the heavy lifting.

The variable resistors I believe are just color adjustment pots. The first time I made an adapter I used a straight DB15 adapter which caused color issues in the picture, so I can't assume voltage conversion is done by this. Though there are tiny ceramic caps on the R,G,B traces which tie to gnd on the Mike adapter.
 
I did a further test of my HotD ROM Board and it passes all the ROM tests which surprised me considering the whole board was gross when I got it. Sound works fantastic also, as this game in its current emulation suffers from poor SCSP emulation of the Model 2A/B/C (Side story: I ported MAME's SCSP code to Supermodel and fixed quite a few problems).
biggestsonicfan -- I have that EGA/CGA to VGA adapter and it works well on my Asus LCD, though I can only get it to display black and white on the old Nanao PC monitor I'm willing to sell and upgrade soon. I know scalers won't work with the gun games, but I wonder if the guns will still track on-screen if you use it in a cab or monitor that has a 24khz tube and a VGA plug...

Upon digging the interwez, I found (and purchased) a mid 90s Iiyama Vision Master 17 MF-8617T that has been reported to work the 24khz signal of arcade games (it's a Japan-made monitor so it was probably designed to support PC-98 machines which are of similar resolution). The manual officially lists the minimum horizontal frequency to be 27 but usually the actual specifications vary in the final product. It's shipping from another country so hopefully it doesn't arrive damaged. Most VGA CRTs made in the '90s onward don't support anything lower than 31.5khz. Fingers X'd.

Also finding out if there are any console light guns that could be modified to play the game. I couldn't get my Master System Light Phaser to track or calibrate in the test menu, but it's possibly a multitude of things -- either I have a broken gun or I'd need to modify it further to get them to actually track by putting the original gun sense board. I've heard of other Model 2 users converting the Saturn Stunner to play it. I reckon it's just a matter of connecting VCC, Trigger, Sensor and GND, modifying the cable slightly, and wiring them to the gun IO and filter board with the appropriate NH connectors. Has anybody tried that?
 

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I know scalers won't work with the gun games, but I wonder if the guns will still track on-screen if you use it in a cab or monitor that has a 24khz tube and a VGA plug...

I legit forgot about that part, oops.

Also what in the world, the memory test screen on top of... gameplay? What is going on there?
 
Yeah the memory test shows the last scene that was loaded before the operator entered the test menu.

Sadly I was canceled on the Iiyama monitor due to high UK shipping costs. Additionally I saw there was a particular Viewsonic monitor from 1996 that supported 24khz -- the PT770. It had a 16.1" Diamondtron tube that apparently was meant for Mac systems, which I guess makes sense cuz some Macs ran 512x384 which is close to a Model 2's resolution. I am definitely on the lookout for one because I also want to natively play FV2 and VF3 on it as intended. Old PC magazines have very useful information regarding the specifications.
 
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