Tv to arcade monitor concerns - Videokarma.org TV - Video

lnx64 · #1 10-16-2012, 05:24 PM

I am going to be making an arcade machine cabinet, and want to use my 27 inch Sharp TV as the monitor. But I have some concerns.

First, it is a fairly modern TV from 2003, and uses a push button power button. How can I make it so as soon as this TV gets power, it turns on immediately without having to press the power button?

Second, I am pretty certain for the best use for an arcade machine, I should probably disable the velocity scanning modulation on this picture tube. For what I understand it is just a coil I need to unplug? I already took care of the RGB picture situation. I am using a RGB to component video adapter, and the picture looks fantastic!

Third and last concern for now, is how can I properly cool this TV considering it may be on for a very very long time? Can I just install a simple fan on the top of the cabinet and it be enough to cool the TV? Or should I pop the back off the TV and run it like that?

lnx64 · #2 10-16-2012, 05:28 PM

Oh, and where can I get good tinted plexiglass to go in front of the TV screen?

ischmidt · #3 10-16-2012, 05:58 PM

I'd recommend asking the folks at BYOAC.com - they're super-knowledgeable about building and modifying arcade cabinets. Regarding the power, check the menus for a "after power failure" setting. Some TVs can be told to turn on after a power failure, which is what you're looking for here.

N2IXK · #4 10-16-2012, 06:09 PM

Absent a "after power failure" menu option, bridging the NO contacts on the power switching relay should work, as should tying the relay control line from the MCU high or low as applicable. I would suggest studying the schematic before modifying the circuitry, though.

AiboPet · #5 10-16-2012, 06:53 PM

As far as running it.....I would leave the back off it. All arcade monitors are "open frame" anyway....and you should already have a back on your arcade cabinet (I built a few MAME machines in the last 20 years or so...I was part of the original MameDev team). For cooloing of the whole cabinet, I'd put a 120mm fan up towards the top of the back cover. The same sort you get at Fry's when you are building a custom gaming computer. a 120mm fan is big enough to run at a low RPM, and you won't hear a "computer fan" running.

As far as the "Velocity Scanning Modulation" thing is....I have no idea what that is. I'd say that if you have a good picture already, and happy with the scanlines, rate, etc.....I'd probly leave it alone. A CRT is deffinately the way to go in an arcade cabinet if you want to stay loyal to that nostalgic look. I converted my Donkey Kong upright to a 22" LCD....and was still able to do pretty good with MAME's video effect command line switches. Your mileage may vary of course...especially if this is an actual arcade board and not a MAME cabinet (MAME would be "Multiple Arcade Machine Emulator" running on USUALLY a PC)

lnx64 · #6 10-16-2012, 11:36 PM

colorfixer · #7 10-17-2012, 01:32 AM

Velocity modulation slightly varies the horizontal sweep to cause the effect of edge enhancement and somewhat greater contrast.

The effect comes by inproving the ability of the beam to make sudden transitions between bright and dark by maintaining spot size as a function of modulating sweep speed.

Purists disdain the feature, and it is said it makes the image harsh and un-natural.

IMHO, it does not look that bad with computer graphics, especially with vintage arcade games, which contain high contrast. The effect can be softened with the sharpness control to a degree.

The images you've posted look very good, as good as any new arcade monitor I've purchased in the last couple of years.

AiboPet · #8 10-17-2012, 06:56 AM

Dunno....those look pretty DAMN good just the way they are from here!

I'd just study the schematics and figure out the "on with power" thing you wanna do so this comes on WITH your PC. Make sure you make a good black paper mask for around the set itself so you don't see the TV cabinet and any LEDs the set may have up front. Bring sound from the source computer and NOT the TV so you don't get IF buzz or anything from the set itself. Use the arcade cabinet's original speaker placements and you will have that PHENOMENAL arcade sound of a big 'ol machine. I miss my original Donkey kong machine (scrambled ROMS)...but I have the cabinet being a VERY loyal MAME machine with the exact same sound and feel of the original by staying with the same monitor angle...and speakers in the same location as the original (but there are two now of course). Only clue it's not a real 1982 DK is the different control panel for all the other games (two joysticks...more buttons....and a Kensington trackball)

lnx64 · #9 10-17-2012, 10:20 AM

Oh this isn't going to be used with a PC.. This is going to be used with a real Capcom CPS-2, and a Sega Genesis with some good arcade ports of games.

I'm going to be making the cabinet from scratch. Go to home depot and literally buy the wood and make it ALL. I plan to put the speakers aiming down from the marque area, and up in there above the TV, a hidden 80's Onkyo amplifier I have lying around.

I may eventually get a Neo Geo MVS to stick in here too.

AiboPet · #10 10-17-2012, 11:33 AM

Ummmm....just COOOOOL!!!

Extra points for Sonic...running on an actual Genesis. Be sure to include PLENTY of buttons on your CP for the NeoGeo games.

lnx64 · #11 10-17-2012, 11:42 AM

Well it's going to have an 8-way joystick (like it should for fighter games), and have 6 buttons, and a start button/mode button (for the genesis).. The 6 buttons alone will be enough for the CPS-2 and Neo Geo.

AiboPet · #12 10-17-2012, 12:00 PM

This button layout (and two joysticks for such weirdness as Crazy Climber)...kept me from keeping the Donkey kong's CP original looking. I could have done that if I was going to only play "4-way joystick and one button" games, but figured if I was gonna build out into a full MAME cabinet....I better have the buttons and two 8-way HAPPS joysticks, as well as a decent trackball for Centipede or whatever.

Cool you were able to get a good RGB output from that Capcom board...and get it to behave for a TV set. I remember ALOT of drama trying to go the other way around and get a VGA card to drive the original Sanyo monitor in the Nintendo cabinet. This monitor used a very odd inverted video signal if I remember correctly. This was like 15 years ago and finally just decided to go with a BIG 'ol NEC VGA monitor (since replaced with a 22" HP LCD). I recapped the original Nintendo/Sanyo monitor, and it still lives on in a VERY rare Radarscope cabinet. The first Donkey Kong machines were retrofitted cabinets of the failed game Radarscope. If you ever see a DK machine that is RED.....it's one of these SUPER rare cabinets. If you ever see a SURVIVING actual Radarscope in this same red cabinet, I have no idea how rare that is.....but a friend has one and is still running my recapped Sanyo monitor in it :-)

lnx64 · #13 10-17-2012, 12:11 PM

Yea I use a JROK RGB to Y/Pr/Pb converter. They work very well, as long as it's not a medium or high resolution screen type game..

I'm right now on the sides though having small arguments with my Dad about where I'm going to put the cabinet once made, he feels I don't have enough room here for it. I figure it puts a TV to use that is just sitting in the garage, and the bottom half of the cabinet could be for storage, since I won't be using a real coin mech. (The genesis an CPS-2 will be directly under the TV on the same level as the joysticks.

AiboPet · #14 10-17-2012, 12:20 PM

I use my DK cabinet for storage of all sorts of hard drives and such. I do have it's original coin mech connected to MAME, but the computer is small and mounted in the exact same (right hand) wall as the original Nintendo boards in their Faraday cage, but only like half the footprint. It's just a micro-ATX in a little "InWin" mini desktop case.

ALOT of room in the whole bottom of that cabinet without the big Nintendo transformer power supply in there. I had to put the original back panel on the machine to keep ALL THREE cats from slinking back there and SLEEPING in the thing :-P

lnx64 · #15 10-19-2012, 01:31 AM

Another thing too, this 27" incher is heaver. I'm going to need to make a bit of support for this TV.

Also, I may have caused a problem on my CPS-2.. Upon trying to replace the "suicide" battery, as it was severely low, I might have accidentally lost power for a moment, as the gator clips delivering temp power came loose. It's right now booting to a garbage screen. Oh no

Well, there's always the Genesis version of Super SF2. It plays as fast as the real one, and has the same controls. But I'll need to see if I can restore the RAM chip that contains the decryption key.

Here's the preliminary design for the cabinet.

I was thinking of possibly just using a universal remote and just aiming it down into the screen, to turn it on and off. Saving time on modifying a working TV.