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Wednesday, April 24, 2013

Rain, Rain, Go Away! I want to work on my Star Wars Trilogy. Fine, I'll work on a 1983 Star Wars instead.

St. Louis weather took a change to the normal for a mid-Spring day and went from a comfortable night that allowed me to work outside to cold and raining with a chance of flurries. So, I spent the time in my indoors workshop.

This is my actual "grail" project. I have wanted a 1983 Star Wars since I was 10. I have been chasing getting one of these, but keep getting blocked by the price tag of one. Every once in a while, someone finds a good working one in some warehouse or person's garage at a steal of a deal. I doubt that I will ever have that chance.

So, I decided to create my own. I had to ditch the notion of getting the real components as the Vector monitor for it doesn't get cheaper than $500. My plan is to just use MAME and have a case cut as close to the original as possible. I have a spare 19" monitor (which is the size of the original), but since I will be creating a new bezel from scratch, I plan on sticking in a 21" CRT. It won't give the same blinding white light when the Death Star explodes, but will be way brighter than an LCD flat-panel.

I bought a broken control panel on auction as that was something critical to the game. After a few repairs and replacements of micro-switches and  potentiometers, I created a custom Star Wars Yoke to USB converter and released the source code and schematics.

 

Last night, I set up a Raspberry Pi with the PiMAME and a copy of the Star Wars rom. After some tweaking and overclocking, the game is playable. However, the PCM audio isn't. All I get is a glitchy distortion. That is something to work on.

My budget for the entire build should be less than $1000. So far, for the yoke controller, Raspberry Pi, the Teensy 2.0 (for the USB converter), cables, connectors, and monitor. I have spent less than $300 of that.


Tuesday, April 23, 2013

Restoring a Star Wars Trilogy


Large... Glowing... Square.... who needs the sun.
After spending the last few weeks trying to get the original projection monitor to stay online for more than 18 minutes. I toyed with the idea of just swapping the guts out of another projection display. I tried enough to get this one to work: resoldered the flyback and other large components, replaced fuses and capacitors on all the neck boards and the power supply, and multi-metered almost half of all the circuits on the board. I really wish I had an osciliscope at home. (Time to start watching ebay/craigslist for one of those.)
It looks better than the original screen.
This decision to go ahead with the projection swap finalized when the SWT at Neutral Zone STL had its monitor kick the bucket. All the tubes on their display seem to glow and be working, so I'm thinking that it was just the video signal board failing before it is sent to the xray emitters. I figure I can use my parts to get that one back to original and then swap my pieces until I can figure out which of mine is bad and then sell the rest to people who need parts.
I rolled my DLP projection TV outside and did an over-engineering project to convert the video. I have one of those GBS-8220 that takes the RGB 15Hz signal to VGA. Well, it turned out my monitor only accepts RGBHL, Svideo, or composite. So, I dug out my VGA to svideo adapter and put it in. Later, I ordered a Weija CV-04 which does the same thing.

Playing this game at this size is euphoric.
Tonight, I am going to move the guts over. By my measurements and quick Sketchup cad-eration, I believe I can get the throw distance correct.

Thursday, April 18, 2013

Seperating two control panel vinyl sheets

Super Friends till the End
While restoring a 1989 Teenage Mutant Ninja Turtles back to its original form from a Captain America and the Avengares for Neutral Zone, I happened upon the control panel vinyl for a Captain America that the vinyl for the TMNT was stuck to.

Fortunately, these were stuck together with what appears to be a spray epoxy. This is relatively easy to separate with some patience, a thin metal ruler (or metal paint scrapper, thinner the better), and some isopropyl alcohol.
Like Daddy used to Drink
Free with Every Lawsuit
Using the short end of the ruler, gently pry apart the layers of vinyl being careful to not bend either sheet as either may be brittle and prone to cracking. Pour in (or spread with a Q-tip) a little alcohol to help soften and de-sticky the glue holding the layers together.

Then, proceed to separate the sheets by moving the ruler in slow pushes. We are talking paraplegic snail slow, giving the glue time to de-bond from one of the surfaces without cracking either.  Think of it as mowing the lawn. Use small strips. Also, don't press hard down to keep from scratching the other vinyl. If you do get cracks, try to work the ruler around them and to the sides and come at them from the direction of the crack.

Note the Grand Canyon sized crack on the left.
For passengers on the right side, please note how happy the people on the left are.

When you get the sheets separated, you can apply liberal amounts of alcohol to the sheets and using a washcloth, scrub off the remaining glue. Some Goo-be-gone will work on this step as well to help get the glue to ball up and removed. Remember, these things were assumed to be permanently covered in sticky soda and sweaty teen hands, so most cleaning style chemicals shouldn't remove the artwork. However, be sure to try the chemical you use on a small section, just in-case your local Walmart switched the isopropyl with battery acid.

Why would someone cover you over?

Best of luck in your endeavors.

John

Adult Super Hero People?