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1 word says it all for me: Impressive

I noted that I would post why I didn't get as much done this weekend as I had planned.

So I picked up another old game: Zaxxon. I won't go into the full storry, but suffice it to say that it was in horrible shape.









Water damage is an understatement! It had a nasty lean just sitting in the garage. The good news is that it does, in fact, work -- mostly.



The brick sprites are missing, but otherwise it is functional.

I picked it up on Saturday, and Saturday evening I went out in the garage and realized that it had to go. The dank, musty smell was over powering. So Sunday I gutted the cabinet and cut it up for the trash.



The parts are worth more than I paid for it, but there was definitely some "what the hell was I thinking" involved.

--SS

Did you save any of the internals?

FireGryphon wrote:

Did you save any of the internals?

Oh yes. The internals were in good shape, considering the outside. Even the control panel and joystick are in pretty decent shape. The boards are mounted on a wood sled which is, luckily, not particle board. Its in good shape. The monitor needs a bath and a cap kit, but otherwise is good.

I'm up in the air as to whether I'm going to hold the parts and wait for a donor cabinet, or part it and contribute to keeping other Zaxxons alive.

I had a Joust like that once. The parts contributed to a rather nice Joust cocktail.
Thanks for posing this stuff, I don't get to the arcade sites as often as I used too, makes me want to dust off my soldering Iron!

Dang. Zaxxon was a heck of a game for its time, but yeah, that cabinet was just too far gone.

SecretSquirrel wrote:

I noted that I would post why I didn't get as much done this weekend as I had planned.
So I picked up another old game: Zaxxon. I won't go into the full storry, but suffice it to say that it was in horrible shape.
Water damage is an understatement! It had a nasty lean just sitting in the garage. The good news is that it does, in fact, work -- mostly.
The brick sprites are missing, but otherwise it is functional.
I picked it up on Saturday, and Saturday evening I went out in the garage and realized that it had to go. The dank, musty smell was over powering. So Sunday I gutted the cabinet and cut it up for the trash.
The parts are worth more than I paid for it, but there was definitely some "what the hell was I thinking" involved. --SS

heh. and finally our worlds come together!

the other site I am on (800% more than TR) is all arcade-based, KLOV.

The Zaxxon you purchased has a huge thread about it from the original seller/owner:

https://forums.arcade-museum.com/showth ... p?t=450093

Enjoy the backstory!

I used to waste untold hours playing Zaxxon on a TRS-80. It loaded from a cassette player.

thegleek wrote:

SecretSquirrel wrote:

I noted that I would post why I didn't get as much done this weekend as I had planned.
So I picked up another old game: Zaxxon. I won't go into the full storry, but suffice it to say that it was in horrible shape.
Water damage is an understatement! It had a nasty lean just sitting in the garage. The good news is that it does, in fact, work -- mostly.
The brick sprites are missing, but otherwise it is functional.
I picked it up on Saturday, and Saturday evening I went out in the garage and realized that it had to go. The dank, musty smell was over powering. So Sunday I gutted the cabinet and cut it up for the trash.
The parts are worth more than I paid for it, but there was definitely some "what the hell was I thinking" involved. --SS

heh. and finally our worlds come together!

the other site I am on (800% more than TR) is all arcade-based, KLOV.

The Zaxxon you purchased has a huge thread about it from the original seller/owner:

https://forums.arcade-museum.com/showth ... p?t=450093

Enjoy the backstory!

Not quite. That's my thread.

Blahpony wrote:

I used to waste untold hours playing Zaxxon on a TRS-80. It loaded from a cassette player.

Wow. I never knew there was a TRS-80 port, to the Model I at that. I actually have a TRS-80 Model I sitting upstairs. Have this strange urge...

What do you mean that the bricks don’t display in the Zaxxon game?

FireGryphon wrote:

What do you mean that the bricks don’t display in the Zaxxon game?

The bricks that make up the wall above, would not show up on the screen. For that matter, neither does the blue "floor". See the screen shot about, for comparison. I haven't looked into it yet as I've been otherwise occupied. As a teaser:



Also, it looks like my 3d printing and arcade interests will intersect again. I have two spools of nylon filament on order to print replacement parts for Pac Man style joysticks. More on that later.

--SS

What would make individual parts of a game not display? What kind of bug is that?

Probably a marginal component on the motherboard.

If it’s a bad motherboard component, how would it work at all? In the PC realm, marginal components mean lack of stability. How could a mobo component make a software glitch?

FireGryphon wrote:

If it’s a bad motherboard component, how would it work at all? In the PC realm, marginal components mean lack of stability. How could a mobo component make a software glitch?

Older arcade games are much simpler beasts in many respects. Think of the bricks as textures. These particular textures are stored in a fixed location in the games memory map. That location is represented on the PCB by an EPROM. If that EPROM gets corrupted, or any of the address decode circuitry dies, then when the game program reads the location that represents the brick texture, it gets back garbage. Maybe its' just black, maybe its random data, maybe it ends up reading some other valid, but wrong data. In any case, what gets output on the screen is incorrect, but it doesn't keep the game from playing.

Similar things can happen in the RAM used for the screen is flaky or bad. The game plays, but the display is garbage, or strangely corrupt. In cases where the EPROM and address decode that actually addresses the game program is broken, or where the CPU itself is bad, you may very well still get something on the screen, but again, garbage. The video output logic is independent of the CPU and will display whatever random garbage is in the video memory.

--SS

Cool. So how do you fix this? Buy a used chip that isn’t corrupt? Fix a solder joint? I can see how emulation is hard now, given that all of these parts work together in specific ways with their own timing and delays, and that all needs to be emulated.

FireGryphon wrote:

Cool. So how do you fix this? Buy a used chip that isn’t corrupt? Fix a solder joint? I can see how emulation is hard now, given that all of these parts work together in specific ways with their own timing and delays, and that all needs to be emulated.

Depends on the cause. Sometimes, it's just an oxidized socket and pulling a chip and cleaning things is sufficient. Sometimes its a cracked solder joint and reflowing it is enough. Lots of times it requires swapping out parts. Most of them, you can still buy, though 2532 EPROMS aren't cheap these days. Some though, are custom chips. In cases like that, you hope someone has reverse engineered them and made viable replacement.

--SS

This weekend I sanded... and sanded... and sanded... Ok, maybe that's a bit of exaggeration, but it sure feels like it this morning. About three hours with 80 grit on the belt sander, with a bit of time from the orbital to get some of the smaller sections and the interior parts.
















I did everything I could with the belt and orbital. The particle board above and behind the monitor had some surface bumps that needed to be take off, and off came the rest of the black. I looked like the paint had been too wet and caused blistering of the particle board. It will never be completely smooth, but it's way better now.

Part of the reason it took so long is I would have to stop every five minutes or so and vacuum the cabinet to get the paint dust off, even with the shop vac hooked up to the dust pickup on the sander. The other purpose was to let the sanding belt cool. If it didn't the dust+hot belt=melted paint, which would gum up the belt in a heart beat.

I made one big mistake. U was working on the back of the cabinet, at the top, where the serial number is (was) stamped into the back edge of the top. The numbers, even though they look it, do not go very deep at all, and 80 grit on a belt sander removes them before you know it. What is more annoying is that I had intentionally left the t-moulding in place to help protect the edges for the heavy duty part of the sanding. It helps keep from causing splintering or from rounding of the edges accidentally. But I didn't think to protect the serial number. At least I have documentation of the original stamping. While I'm not trying to do an absolute, museum accurate, restoration, I might just have to see about re-stamping the serial when I'm done.

The next phase will be a quick run back over everything with 120 grit, then working on all the corners and hard to reach spots with oscillating multi-tool with sanding shoe. After that, a pass over everything with 240, using just the orbital and multi-tool.

Then the bondo comes out. The main sides and front are in quite good shape, with a few dents here and there. The edges that aren't protected by t-moulding, on the other hand, are well splintered along most of their length. Bondo gets sanded down, up to 240 grit.

We'll see how that turns out and either prime it and run another pass over everything with 320 grit.

--SS

As a follow up to my earlier coin door post....

A few more coin door before and after pics.









I a new lock on order and I need to install it and the tilt switch, as well as reconnect the tilt switch wires, which had been cut off and taped together. I also need to clean up and zip tie the rest of the wiring.

Unfortunately, I didn't take any good close ups of the control panel before I started on it. But here is a before pic to give you an idea....







I cleaned the buttons, but as you can see, they are still yellowed with age. I'll probably try and retro-brite them at some point, but ordered a new pair to put in their place. The joystick needs miscellaneous parts, but is at least functional. The red ball has a dark tint to it, even after being cleaned well. I'm kinda assuming that's partially just the color it is and partially assuming its 30 years are arcade hands and there's not much more to do. It will stay though as it is original to the machine, as best I can tell, and unlike the buttons, keep it seems much more deeply tied to restoring the machines.

Its hard to tell, but the new buttons definitely look nicer. This picture was taken at night under warm white light, so the buttons aren't as white looking as they are in reality.

Finally got around to putting my new width coil in place.



Worked like a champ. Was able to tune the width as needed. Coil barely gets warm. Might need to rethink the design for my printed mounts as they allow for a little much movement for my taste, especially when adjusting the slug. You really don't want the coil rotating and shorting a terminal to the monitor frame.

The picture isn't completely tuned, but I'm not going to mess with it much more until its back in the cabinet. Pretty happy with it. Ok, actually, I'm thrilled with it.



Quick video. Movement sucks as I'm glancing back and forth between my phone and the screen and there is probably a half second lag between what is actually happening and what's being shown on my phone screen.

https://youtu.be/CaOo9H9P9cA

--SS

Bravo! This thread is epic!

just brew it! wrote:

Bravo! This thread is epic!

I get a four day weekend for Memorial day this year, I while I get back from a business trip late Thursday night, I really want to spend the long weekend painting. Guess it's time to order the cabinet stencils.

--SS

The screen looks awesome. Great work all around!

Little bit of Zaxxon follow up. I had an hour free this evening so I cleared Ms Pac Man off the work bench and lugged Zaxxon up. Luckily they have similar monitors and I could plug Zaxxon into my refurbed Ms Pac monitor. The Zaxxon monitor is so nasty, I won't bring it inside before its clean.

Fired it up and the picture is gorgeous. All the sprites are there.





I don't know if the moving around "fixed" it, of if the problem is in the display sitting in the corner of my garage. Regardless, I at least have a fully working board set.

Video of the start of the attract sequence.
https://youtu.be/WnaSANm6CTs

Probably a corroded socket or cracked solder joint, and moving it jarred something just enough to make contact again. I've had pretty good luck isolating issues like that by gently tapping on circuit boards while the system is running (using something non-conductive!), to see what area seems most sensitive.

AKA "The Fonz" approach.

Percussive Maintenance

SuperSpy wrote:

AKA "The Fonz" approach.

Captain Ned wrote:

Percussive Maintenance

Not quite. That's where you just give the whole thing a really good hard whack, and don't worry about root causing the issue. And yeah, I've used that approach too, when I didn't care enough about a piece of equipment to deal with a permanent repair!

At a previous job, there was a particular model of Viewsonic LCD monitor on nearly everyone's desk which tended to develop intermittent issues after a few years. Giving them a good whack on the side of the bezel would generally get them working again for several days.

JBI wrote:

Not quite. That's where you just give the whole thing a really good hard whack, and don't worry about root causing the issue. And yeah, I've used that approach too, when I didn't care enough about a piece of equipment to deal with a permanent repair!

Yeah, and it's actually a real diagnostic thing that the professionals did!

Minicomputers were a bunch of individual boards of (semi) discrete components too, and were really expensive and important too.

And, yes, one of the diagnostics, both in design and field engineering, to diagnose the very worst sort of bug, the intermittent and idiopathic kind, was to "tap" test the individual boards while it was running to see if that would reliably induce the behavior.

If it did, you didn't just localize it, but pretty much demonstrated that it likely was socket/joint issue too.

You could probably find references to this in field manuals, I'd imagine.