Could this CRT monitor be used for arcade games?

[tobiasbp]

Hello monitor gurus.

In my local hacker space today, I fell in love with a small CRT monitor. It would be perfect for a small arcade machine. Knowing very little about these things, I'm unable to really evaluate the potential of the monitor for arcade games.

The previous owner says the monitor is monochrome, but I see a trio of a red,  a green and a blue wire running from the chassis to the neck board? Would this not indicate a color monitor? The monitor has  a video input and a video output (??) on the back (Looks like BNC connectors to me). There is also a switch marked 75 ohm (on/off).  The front has four knobs: Contrast, bright, H hold, V hold (The names are ob the pcb). The tube is a Toshiba. I can't find any markings of interest on the main board besides (c) 1986. Most of he monitors cover is missing, so there is no visible manufacturer or model number.

Monitor as seen from the front. Arcade button for size comparison:


Looks like RGB from the chassis to the neck board to me:


In-/outputs and switch on the back:



Would this monitor not be great for a small arcade machine? If it's monochrome, I could build a mini space invaders replica complete with colored cellofane on the monitor!

Any hints/suggestions much appreciated.

Tobias 

[Rickn]

So what I can see from the pictures:
Those leads you show come from the yoke, Red and Blue Horizontal.. Yellow green vertical.
Seemed like the rings on the neck of the tube only have one set of 2 rings. If that is so for sure monochrome, these are basically centering rings, The signal input is BNC, again indicating not monochrome, but it will oly accept a composite video input. This means 1 signal input line that contains all sync info as well as picture info.
If I am right best you can do with this short of taking it to the curb, would be to buy an NTSC to RGB converter, tie all 3 lines (RGB) together and now we are back to monochrome... a lot of work and honestly....

Good luck
Rick

[tobiasbp]

Hello Rick.

Thank you for your reply.

I have taken close up photos of the neck of the tube. Maybe you'll be able to tell if the monitor is indeed monochrome (I'm afraid it is)?

If the monitor is monochrome, would I not be able to combine the R,G and B signals coming from a computer running MAME and feeding that signal along with the sync directly to the chassis/monitor bypassing the BNC input?





Thank you,
Tobias

[ed12]

hi
as rickn pointed out to u those are the yoke wire's
they have nothing to do with the video....period.

they control horz/vert defecltion
to the yoke

your video input would be the bnc conector

ed

[Ken Layton]

Looks like you have a security camera monitor which accepts composite video through that BNC connector.

[mgb]

Yeah that's definitely just a monochrome cctv monitor.
They're made to run 24/7 but most old CRT ones that I see have a whe bunch of screen burn.

[tobiasbp]

Thank you for all your comments.

As far as I understand you, these are the facts:

• My idea of somehow "injecting" a monochrome "RGB" signal somewhere on the chassis makes no sense.
• The monitor should produce a picture when fed composite video on the "video in" BNC.

I have s-video out from my MAME machine. Is it possible to convert the signal to composite for use on the monitor with a simple adapter like this?

http://www.bestbuy.com/site/Dynex%26%23153%3B---Composite-Video-to-S-Video-Adapter/8470139.p?id=1184768166778&skuId=8470139

Edit: VGA -> "RGB" in first item in list.

[tobiasbp]

I have tested the monitor with an Arduino and the TVOut library. Monitor works fine. Some burn in.

I wonder if it's possible to get acceptable picture quality on the monitor with MAME running the old monochrome arcade games from the 70's?

[mgb]

I think it'd be fine for monochrome games from the 70s.
Those were basically black and white televisions with composite video.

There are adapters for s video to composite.
http://www.amazon.com/gp/aw/d/B0009EXWQQ

You also need an RCA to BNC connector
http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10430&cs_id=1043002&p_id=4121&seq=1&format=2

Cctv monitors also typically have another BNC for passing video back out. Make sure you terminate it. This is done by either turning on a termination switch that may be on the monitor or by using a 75 ohm BNC terminator.
Otherwise you may get signal reflection

[mgb]

Actually I see that monitor does have a 75ohm termination switch so if you are not using the video out, just make sure that switch is on

[tobiasbp]

Thank you for your comments on the 75 ohm terminator. The switch was off when I tested the monitor earlier (Looked fine to me). I will switch it on and try again.

[mgb]

Yeah most times you won't see a difference wether its terminated or not

[Gray_Area]

Geez, why?