ROTAVATOR: manual rotating LCD

[Zobeid]

I've almost finished my cabinet with a rotating monitor (project thread here: http://forum.arcadecontrols.com/index.php?topic=78150.0) and figured I should jot down some notes and observations.  So. . .

Why rotate?  Why not just put a great big monitor in the cabinet, so even the vertical games come out a reasonable size?

That was my first idea.  I knew I wanted a LCD, and I didn't like the idea of a widescreen -- especially in a classic-sized cabinet, which was my goal.  If I went 4:3 then the biggest I could get was 21-inch, and I'd pay a premium for that.  Either way, horizontal games would appear much bigger than vertical games.  It nagged at me.  So I started thinking about rotation.

My idea was to use a LCD monitor and a lazy susan bearing to create a simple, manually operated rotating mechanism.  With LCD there's no huge mass to support, no degaussing problem.  The lazy suzan bearing is cheap and readily available.  The rest is basic woodworking with a router, which would become familiar to me while building the rest of the cabinet.

I have great admiration for the guys who are doing motorized rigs with custom software to control them.  I think what they're doing is amazing.  As I followed the threads on their projects, I realized I didn't want to go that way.  I wanted to keep it simple, and what they were doing wasn't simple.  Also, I don't think any motorized system is likely to be as fast and convenient as a manual system where you just grab the monitor and whang it around into the desired position.  It takes about three seconds on my cabinet.

The monitor frame is constructed like a box or cage.  There are two circular pieces: one solid, the other one with a cut-out for the monitor.  Then there are four 1.5X1.5 spacers between the circular pieces, joining them together.  Very early in the design phase I realized I needed both of those circular pieces.  One has to go in back to provide a solid connection with the lazy susan bearing and the support board, and the other has to go in front and provide a solid connection for the bezel and handle.  It didn't matter whether the monitor was connected to the back circle (with a VESA mount) or the the front circle (with a panel mount).  Either way, both pieces would be required for the design to work.



Cutting the circles was done following advice here on BYOAC.  I drilled a 1/4" hole in a sheet of 3/4 plywood, then improvised a compass with a small piece of wood and drew the circle.  I rough-cut it with a jigsaw.  If I didn't care how it looked, I could have left it at that and it would have worked (and the rough edges would have been concealed behind the bezel frame anyhow).  To make it pretty I bolted a piece of 1/4" plywood to my router, bolted the other end through the center of the circle, and soon I was trimming a smooth curve.

Making it stop at the vertical and horizontal positions was easy enough, using a couple of roller catches (commonly used with cabinet doors).  Magnetic catches would probably have been even easier, as they wouldn't have needed careful alignment.



The monitor I chose was a Happ 19-inch arcade LCD.  It uses panel-mounting to the front circle.  This monitor has been excellent.  The mounting is versatile and clean (you never know if a VESA mount will be centered), it doesn't have any large or off-center frame hanging off the bottom or sides, it comes on whenever power is applied, and the adjustment controls are on a small panel at the end of a cord, so you can place them wherever is convenient.  A 19-inch monitor is the same size used by most of the older classic games, so it's authentic in size and aspect ratio.



The bezel is in two parts: the tinted "window" that covers the monitor and rotates with it, and the fixed frame that overlaps around the edges.  Both are attached with velcro.  So, if I want to access the monitor for any reason, I just remove the control panel, then pull away the bezel frame, then pull away the bezel window, and I'm there.  The bezel window itself has two slots allowing it to slip around the handle (an ordinary cabinet or drawer handle, by the way) as it goes on and off.

The bezel is tinted dark gray.  This was supposed to improve the black level of the LCD, and it does.   It's so dark, I had to crank up the contrast on the LCD and then further adjust the brightness and contrast in my NVidia control panel before I was happy with the look.  An advantage of a really dark bezel is that the ugly wood and screws behind it are pretty well hidden.  I was going to have some kind of dark material behind it to cover them up, but it turned out to be unnecessary.

The surrounding frame is spray-painted blue.  The overall look turns out to be quite retro.  It reminds me of 1970s computer equipment, or maybe radar equipment from a control tower.  It's perfect for playing Radar Scope.



In the beginning I wanted to use some special switches to keep my front-end synchronized with the screen position.  I wanted to have two switches: one to switch the front-end to a horizontal layout, another to switch it to the vertical layout.  The switches would be tripped when the monitor rotated past them.  I discovered that Mala didn't support this.  It only supported a single button to switch between vertical and horizontal layouts.  I could install a single switch and have it tripped by the monitor movement -- but I was sure it would get confused and get into situations where it switched the opposite of what was intended.

I then decided to simply set up a button on the control panel and let the user push the button to switch layouts.  This turned out to be a great idea.  I discovered Mala has an option to automatically switch its layout to match the last game played.  So actually it's fairly uncommon that I ever need to push the button.  Most of the time it works like this. . .

Let's say I am browsing my list with the monitor horizontal.  All the horizontal and vertical games are mixed together in the same list, I don't worry about that when I'm browsing.  So I pick, for example, Pac Man. . .   The game starts up, and then I suddenly realize everything is sideways on the screen.  I reach up to the big handle and whang it around to the vertical position -- takes about three seconds.

When I get tired of Pac Man and exit, Mala automatically switches to vertical layout, and I can continue browsing without having to push any buttons or change the monitor.  It's perfectly convenient.  I've read comments from a few guys with a rotating monitor rig, who said after the novelty wore off they didn't even rotate it anymore; they just ran everything horizontal because rotating was too much hassle.  I can't imagine that ever happening with this cabinet.

[ediblegod]

That's SWEET!

I'd love to see a video of that thing in action.

[Ummon]

Hopefully the brightness being up won't overtax the display over time. Though you can see a little in the picture above, what's the deflection angle on this one you have here? And why did you get this vs a consumer LCD?

[Timstuff]

This motorized monitor setup is pretty wild...

[youtube]DpN882epeMQ[/youtube]

Anyway, nice job.

[Blanka]

Is the Happ 4:3? Never knew 19 inch was available in 4:3. I only know 4:5 1024x1280 displays at that size.
How do you handle the heat? Seems the monitor is pretty much enclosed completely. My LCD has to get rid off quite a bit of heat.
@ Timstuff? Who made that motorized setup? Nice video, but I like a link to the project as well.

[lettuce]

Whoo, thats friggin awesome! If i ever build another cab i think ill go down the LCD 4:3 route, but not sure what the max size is for a 4:3 LCD, i would really want anything smaller than a 24" really, and all this rotational screens has got me thinking 

[Blanka]

@ Lettuce: 21.3 inch is max. Either the Samsung 214T, the Eizo S2100 or the Nec 2190 are your options.

[Zobeid]

Hopefully the brightness being up won't overtax the display over time. Though you can see a little in the picture above, what's the deflection angle on this one you have here? And why did you get this vs a consumer LCD?

Yes cranking up the backlight will reduce its life span somewhat.  I figure I won't be running this all day long every day (like I so often do with my computer), so it should last a very long time.  I've been running it a lot while configuring it and trying it out, of course, but I'm sure eventually the novelty will wear off.

Why this instead of a consumer LCD?  If I bought a desktop LCD off someplace like Newegg, there were a lot of uncertainties.  Would the VESA mount be centered?  Would the adjustment controls be positioned where I could access them after the cabinet was put together?  Would it come on automatically when power is applied?  With the arcade monitor there was a lot less uncertainty.  It's designed for use in a cabinet.

It might be different if I lived some place with a computer store where I could examine the monitors hands-on and pick one.  But I live way out in the middle of nowhere, it wasn't practical to do that.

I have to mention something here that I forgot when I started this thread. . .

The Happ LCD has great viewing angles from the top and sides.  The view from below is not so great.  When it's in horizontal mode there's no problem.  When it's in the vertical mode and you are standing directly in front of it, then it's okay.  When it's vertical and you are standing a bit to the right, in the player two position, then it's okay.  When you are standing a bit to the left -- in the player one position -- then it's marginal.  It's just starting to go dark at the edge, when you look at it from that angle.

For most one-player games I tend to configure it to use the joystick on the left and the buttons on the right.  That puts me centered in front of the control panel.  It's only the two-simultaneous-player vertical games that can be a little awkward.  So. . .   If you are playing Raiden, Truxton, or any of the many many other games in that genre, and you're player one, then it's marginal.  And most of the time, obviously, you will be player one.

In a perfect world it would be better if the monitor rotated counterclockwise, to the left instead of to the right.  Then the viewing angle would be marginal for player two.  But Mala and I think most other software assumes it rotates right.  (And I'd already made my Rotavator to rotate to the right by the time I noticed this, anyhow.)

The other thing somebody could do is configure player one controls to be on the right and player two controls to be on the left.  But. . .   That would be weird too.  It would confuse people.  So, I shrugged and decided I can live with it the way it is.

[boogieman]

Awesome!  Great job!   

[Zobeid]

Is the Happ 4:3? Never knew 19 inch was available in 4:3. I only know 4:5 1024x1280 displays at that size.

Yeah, it's a regular 4:3 aspect ratio.  Full specs here:

http://www.happcontrols.com/monitors/49260300.htm

How do you handle the heat? Seems the monitor is pretty much enclosed completely. My LCD has to get rid off quite a bit of heat.

It's not enclosed completely.  There are spacers above and below, and either side, made from 1.5x1.5 wood, but the corners are wide open, the openings big enough to easily stick your hand through.  The air can flow by convection in through the bottom corners and out the top.

[Blanka]

If I read that specs it's pretty 1280x1024, and thus 5:4!
They really should offer any of the 21.3 inches in a cabinetmount. These screens are really kick ass. 1:1000 contrast and 178/178 viewing degrees.
About the centering of the VESA mount, as these consumer 21.3 inches all pivot, they have centered mounts too.
Does anybody have a link to the designer of the motor-rotated mame video yet?

[Zobeid]

Hmm, interesting point. . .

Pixels are not always square, so the only way to be sure is to measure the screen itself.  According to my tape measure:

14.75" X 11.75" = 1.25 = 5:4

Yep.  That's a surprise.

I'm totally puzzled now.  It looks normal to me.  The only aspect ratios I've ever heard about are 4:3 (NTSC), 16:9 (ATSC) and 16:10 (widescreen computer monitors and some HDTVs).  I've never heard of a 5:4 monitor before.  I had no idea I had something so odd.

I tried messing with some settings in MAME to see if I could get it to display an actual 4:3 image, but no luck.  What's going on here?

UPDATE:  It's SXGA.  See here. . .   http://en.wikipedia.org/wiki/SXGA

I'd never encountered this before.  I found the key is to set Windows resolution to the actual native resolution of the monitor, to 1280X1024.  After doing that, MAME began displaying its games in true 4:3 with a very narrow black border at the top and bottom.

[Ummon]

Yeah, that's a helpful figure, isn't it? Hence, most monitors haven't really been 4:3 for a while. Here's the page I found. What's interesting is it shows 2048x1536 as 4:3 and my PC monitor here does both. You can tell the difference though by paying close attention to the width. Even in pictures, you can tell the width on older PC monitors, and especially TVs, is that much more than on some later model PC CRTs. I had a '99 or '00 Gateway or something, and it just looked wider than my Dell Trinitron. Well, it was.

As for the borders in Mame, just deselect 'autoselect aspect' in the screen tab.

[Blanka]

And there is a zillion of non-square pixel standards as well.
The image on Wikipedia is not correct. CGA and NTSC are 320x200 and 720x480, but they ARE 4:3. So their pixels are non-square. Also with new plasma's, they are 1080x1024 pixels,  but they ARE 16:9. The pixels are almost twice as wide as high.

[mrclean]

Let's say I am browsing my list with the monitor horizontal.  All the horizontal and vertical games are mixed together in the same list, I don't worry about that when I'm browsing.  So I pick, for example, Pac Man. . .   The game starts up, and then I suddenly realize everything is sideways on the screen.  I reach up to the big handle and whang it around to the vertical position -- takes about three seconds.

When I get tired of Pac Man and exit, Mala automatically switches to vertical layout, and I can continue browsing without having to push any buttons or change the monitor.  It's perfectly convenient.  I've read comments from a few guys with a rotating monitor rig, who said after the novelty wore off they didn't even rotate it anymore; they just ran everything horizontal because rotating was too much hassle.  I can't imagine that ever happening with this cabinet.

Ahh how do i do this with MaLa what settings do i need to use etc I got MAME to automatically rotate

[spystyle]

Awesome