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EPOCH Astro Command - dead or dying

 
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Mon Jan 11, 2016 11:56 am    Post subject: EPOCH Astro Command - dead or dying Reply with quote

Hi all!
I haven't posted here in a long time, not due to lack of interest in handheld games, but simply lack of time.
I'm currently working on a dead EPOCH Astro Command that I bought long ago not working.
I do a lot of electronics repair, mainly on vintage cartridge and disc-based systems since they tend to have a lot more problems than these old handhelds.
I finally got around to working on this dead EPOCH Astro Command.
I've cleaned - and had to file - the rusty battery contacts. With a voltmeter I am able to verify power inside the unit. I was able to get it to come on occasionally, but the screen was usually showing incorrect gameplay, the screen was also flashing rapidly, not affecting the gameplay. Then it quit working altogether. I've swapped batteries with no result.
I didn't do any serious searching for schematics, since I figure they just don't exist.
I also own a working Radio Shack version, I carefully opened that one and found they were almost exactly the same parts on the boards. And started doing voltage comparisons with a voltmeter on all the parts between both the units. Of course, there were differences between the two units in voltages, starting right at the power supply section where I "guess" it converts dc to AC for the VFD and sends dc to the other circuits. I checked each part in that area by removing and testing. First, I replaced all the electrolytic caps with new ones. Still not working, and desperate for results, I started swapping parts from the working unit, assuming that when the dead unit started working again, I would know which part was bad. I swapped damn near every part in that thing with parts from the working unit and it still won't turn on! The working unit is still working, so I know the parts are OK. The only part I haven't swapped is the main IC chip and crystal, that I wouldn't be able to find a replacement for anyway.
Now, the only thing I can think of to really destroy one of these units is to plug in an incorrect power supply. But wouldn't that fry one of the transistors, or resistors or diodes before frying the main IC chip?
Anybody have any ideas or links or whatever? Even another broken one they are willing to sell? Thanks!

PS: I moved this post since I thought here was a better place for it.
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Rik
Site Admin


Joined: 07 Oct 2005
Last Visit: 25 Mar 2024
Posts: 1932
Location: California

PostPosted: Mon Jan 11, 2016 10:07 pm    Post subject: Reply with quote

I have a game like that too, replaced everything I can think of and it still won't work (it never did anything in my possession). The only thing left to assume is that the CPU is indeed fried. Even without the VFD display or the little transformer that powers it, the game will work properly and make sounds. So if you can't hear it trying to play properly, then it's nothing to do with the display or it's circuitry.

The only other possibility is a short on the circuit board somewhere (either a contact that's corroded away somehow, or something bridging a gap that shouldn't be).

Normally when I get a dead game, it's a transistor or two likely blown from an incorrect power supply. I don't know if the right kind of bad power (high voltage, AC instead of DC, something drastic like that) can get through and actually damage the chip, or if it was something else that did it on the game I have. I never tried swapping out the chip with another, I Just kind of stopped messing with it and used it for parts. Smile

If you are comfortable with removing chips, try swapping them. I'd try the 'bad' chip in the 'good' game first, just in case there's a short or something that will fry your known good chip...

Generally, I go after transistors, diodes, and then cold-solder joints/close inspection of the circuit board. If none of those seem to yield results, that's where I stop (unless the game is just insanely rare or something).
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Tue Jan 12, 2016 6:46 am    Post subject: Reply with quote

Thanks for the reply! I know this machine is not rare in any way, I just really hate seeing any of them die. There will never be anything like this built again, so I feel it's definitely worth the time to try and save it. Plus, I actually ENJOY fixing electronics, I know that's a bit crazy.
Rik, you brought up some interesting points. The first thing I did to avoid going insane while working on it was to disconnect the speaker, so I'll connect that again and see if any gameplay is going on (minus the display). Sometimes I get so wrapped up in the details of troubleshooting that I miss the obvious. That's why it's good to talk it out and get an opinion.
In all your experiences, have you ever had a VFD display die? Don't they usually just start to fade out? I've found a few fading displays in other stuff like tape decks, vcrs, etc. I may swap the main chip or crystal yet and see what happens.
I'll do a bit more checking the board for broken traces and sold joints, but it's such a good quality and simple board that I find it hard to believe. But anything is possible I guess after so many years. The best part about these old games is that most of them still work today while yesterday's TV and smartphone already died, haha!
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Rik
Site Admin


Joined: 07 Oct 2005
Last Visit: 25 Mar 2024
Posts: 1932
Location: California

PostPosted: Tue Jan 12, 2016 7:23 pm    Post subject: Reply with quote

I've never had a VFD just die, unless the glass was physically broken. I suppose it's possible the seams between the glass plates could fail, but I've never seen that happen...
With heavy use, they will fade, and usually not even evenly. What ever parts of it are on the most will fade faster than others. This takes years though, so unless its been on constantly, it's usually not an issue with these games. There's other internal damage that can happen like the filament wires can break which will cause an area of the display to be very dim... But they definitely fade out over time rather than popping out like a light bulb.

For solder joints, take a look at the final pictures here:
http://www.handheldmuseum.com/Coleco/ColecoRepair/index3.html
I would have never suspected that darkened area to actually be corroding metal causing the display failure. Fortunately it was easy to trace since I knew exactly what part of the display wasn't working, but anything on the circuit board that doesn't look 100% normal could be suspect.
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blanka
Atari Cosmos


Joined: 14 Dec 2010
Last Visit: 13 Oct 2022
Posts: 561
Location: Eindhoven, the Netherlands

PostPosted: Thu Jan 14, 2016 12:14 am    Post subject: Reply with quote

Just checked my schematic database, but there is no Astro Command in it. If I had time, I would add it, since I think it is an Epoch-NEC D552 design, which is not yet in it (many games share similar schematics). Probably the nearest one would be Bambino Safari.

Which MicroController does it have?
Is it a pull-up resistor design, or one with internal high-voltage switching?
Which transistors make up the PSU?
C945? D882? C1214? D789? 2SD545? 2SC536? C1470? D471? C1815?
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Fri Jan 15, 2016 6:04 am    Post subject: Yay, I made it worse. Reply with quote

Wow, thanks for all the attention, though I probably don't deserve it. I couldn't tell you if it's a "pull-up resistor design, or one with internal high-voltage switching". I'm just not that electronically-educated. I looked through rik's repair photo page, and the main board looks closest to this one: http://www.handheldmuseum.com/Guts/Grandstand-BigGameSoccerGuts.jpg The Microcontroller has the resistor arrays along both sides, and the power supply has the round transformer, etc.
I finally had a chance to look at the game again last nite for a minute and noted that the Microcontroller is D553C 202. The transistors in the power section are D882 and C2785. The rest of the transistors are C2785. I reconnected the speaker and verified there was still no game play going on. Still dead.
But, as I was looking at it with fresh eyeballs, and flipping over the main board again, I saw that the ribbon cable going from the control / switch board was frayed and barely connected, then some of the wires broke entirely. I'm guessing I flipped it over too many times, so now I have to fix that. But, it made me wonder if one of those wires were broken when I started, could it be possible that the main board just wasn't getting enough voltage? I had been measuring the correct battery voltage at the AC connector, but when I measured at the internal power supply parts I saw really low voltages and, then rather high voltages coming out of that circular transformer. So, I guess the power goes through the control / switch board, then through the ribbon cable to the main board. I'll fix that cable then let you know. Hopefully that is the problem.
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blanka
Atari Cosmos


Joined: 14 Dec 2010
Last Visit: 13 Oct 2022
Posts: 561
Location: Eindhoven, the Netherlands

PostPosted: Sun Jan 17, 2016 12:30 pm    Post subject: Reply with quote

Yes, power always goes through the control PCB. Hope for you it is tye problem.
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Mon Jan 18, 2016 6:40 am    Post subject: Reply with quote

Final Captain's Log: After repairing the ribbon cable from control board to main board, and rewiring from battery compartment to ac jack, the unit is still dead. Measured full voltage all the way to the main board, but still nothing. Reflowed all solder joints, but all for nought. I didn't try to swap microcontroller, for fear of ruining my good game. I've decided that I've spent enough time trying to repair, so it's on to new things. I have an idea to use the Astro Command cabinet to built a small arcade computer. I'll keep you updated on that progress. Thanks very much for all of your help!
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Lukasz604
Mattel Football


Joined: 18 Jan 2016
Last Visit: 01 Feb 2016
Posts: 12
Location: Burnaby BC Canada

PostPosted: Thu Jan 21, 2016 11:35 pm    Post subject: Reply with quote

That's too bad about the game. Its in a better place now in vintage heaven.
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pjwhoopie
Tomy Blip


Joined: 22 Dec 2015
Last Visit: 24 Jan 2016
Posts: 1
Location: maryland

PostPosted: Sun Jan 24, 2016 4:49 am    Post subject: Reply with quote

Lukasz604 wrote:
That's too bad about the game. Its in a better place now in vintage heaven.


Better yet, repurposing the housing is a nice idea for a 2nd life.
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Rik
Site Admin


Joined: 07 Oct 2005
Last Visit: 25 Mar 2024
Posts: 1932
Location: California

PostPosted: Sun Jan 24, 2016 6:13 pm    Post subject: Reply with quote

And save all the little parts inside. The rubber things under the buttons, any springs, the little speaker. Anything that might work as a replacement part on another game if you need one later on. I have a little box full of all kinds of doodads from games I scrapped.
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Wed Feb 10, 2016 6:21 am    Post subject: Astro Command into the Future! Reply with quote

While I am currently enjoying the crap outa my recently repaired Entex Stargate, I also began tearing down the Astro Command machine that previously eluded my desperate attempts to repair. I took one last stab at determining what caused it's demise, but I could still find nothing.

So, I completely stripped it down and removed everything to prepare for my first emulator machine using a Raspberry Pi and Mame. I'm trying to use as much of the original machine as possible, so I kept the original buttons so it still has a vintage look and feel, plus I found that the magnifying lens behind the window makes a mini lcd look really sweet. I'm also saving the cool transparent space scene for another idea.

Originally, I planned to put the raspberry pi in the battery compartment, so I could access the usb ports at any time, but the display looks much bigger when pushed all the way to the back of the cabinet, so the Pi will have to sit at the floor in front of the lcd display which might make it difficult to update software in the future.

Since I've always hated the clunky joystick on this machine, I replaced it with a thumbstick from a PS3 controller. I cut the original controls pcb and button plastics in half to make room for it. Next, I'll wire the original buttons to two of the PS3 buttons and mount the PS3 controller board inside too.

Since the PS3 controller I disassembled is an Afterglow brand with lots of leds, I'm going to spread out the leds inside the game to give it a space-ace look. I'm thinking if I cut and spread out the space scene transparency and backlight it with leds inside, it'll give it some real artistic depth.

Not sure how to get more buttons without cutting some holes in the control panel, but I may need to. I've been taking pics, so I'll post em when done. Wish me luck!
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Tue Aug 30, 2016 7:58 am    Post subject: Astro Command MAME machine - complete! Reply with quote

Finally completed my Astro Command MAME machine. For anyone who cares, this was a game that I did everything possible to resurrect from the dead, including swapping parts from another machine in a last desperate attempt to find the bad part. Anway, I gave up and decided that the case was way too nice to scrap, especially since it had that great magnifying lens and transparent outerspace / starship control panel artwork inside. So, I had a vision. Turn it into a MAME machine using a Raspberry Pi, like everyone it seems is doing these days.

So, I got the Raspberry Pi and set up the software to my liking, but that was the easy part. Since I had never used a Pi before, I spent more than a month of weekends trying to figure out how to power the screen, audio amplifier and speakers, and additional LEDs, off a single adapter and add a new joystick and more buttons. Then, figure out how to get everything to fit in that case. The case seemed really big at first, but by the time I was done, I had dremelled out everything inside except the two posts that held the original circuit board / flourescent display.

I never liked the clunky joystick on the machine, so I was determined to replace that, and I needed at least one more button for some arcade games. I tried using a PS3 controller first and had the thumbstick working, but decided it was too modern-looking. Then, I saw this excellent all-aluminum joystick called Joystick-It for pads. Found a used one and was determined to make that work somehow. Two completely disassembled and sliced and diced Sega Genesis controllers later, I found a way to split the circuit board of the Genesis buttons and thumbpad, and mount the Joystick-It directly to the top of the thumbpad, to make a really responsive, totally non-clicky (I hate clicky buttons) joystick and controls. For anyone who wants to try it, the Joystick-It can be unscrewed and there's already a hole in base. So, you can easily put a screw through it to mount, then screw the stick back on.

I could have used the GPIO pins on the Raspberry Pi and wired the controls directly and all, but I wanted to be able to unplug the usb of the controls any time, so I could plug in two more controllers, HDMI to the TV and play with others.

I'm not entirely happy with the way the buttons look mounted on the top, but it'll do for now. I wired three LEDs from the Pi 3.3v pin and mounted them in various exciting places inside. Finally, I cut the transparent outerspace / starship control panel overlay and mounted the pieces around the screen to be lit by the LEDs. I used slowly changing color LEDs so the colors all over are constantly shifting.

For the controls, I mapped the Emulator menu to the original Start button, Add Coin to Start/A button combo, Player 1 Start to Start/B button combo, Quit to Main Menu to Start/C combo. So the whole thing can be played completely stand alone.

OK, so I can no longer run it on batteries, since there was no more room inside to experiment with that, but I can live with a power adapter since I'm not taking this on the bus anyway.

Let me know if anyone cares, and I'll post some pictures!

I can only hope that some future generation finds this in a storage unit someday, turns it on and says, "What, only 1500 classic arcade games? How archaic."
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Rik
Site Admin


Joined: 07 Oct 2005
Last Visit: 25 Mar 2024
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Location: California

PostPosted: Mon Sep 05, 2016 3:41 pm    Post subject: Reply with quote

Oh, definitely post pictures! Inside and out, I'd love to see the entire thing! Cool
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lordsardonyx
Coleco Pac Man


Joined: 04 Feb 2010
Last Visit: 05 Sep 2019
Posts: 36

PostPosted: Sun Sep 11, 2016 1:24 pm    Post subject: Granstand Scramble - MAME machine - complete! Reply with quote

Here's some glamor shots of the final system and the guts!
I'm such a meathead... I noticed I was calling it an Epoch Astro Command
the whole time, when it is actually a Grandstand Scramble. Doh!

http://paganflames.com/shots/scramble_mame_gameplay1.JPG
http://paganflames.com/shots/scramble_mame_guts1.JPG
http://paganflames.com/shots/scramble_mame_guts2.JPG
http://paganflames.com/shots/scramble_mame_guts3.JPG
http://paganflames.com/shots/scramble_mame_bootup.JPG
http://paganflames.com/shots/scramble_mame_gameplay2.JPG
http://paganflames.com/shots/scramble_mame_gameplay4.JPG
http://paganflames.com/shots/scramble_mame_indown.JPG
http://paganflames.com/shots/scramble_mame_inleft.JPG
http://paganflames.com/shots/scramble_mame_inright.JPG
http://paganflames.com/shots/scramble_mame_Intop.JPG
http://paganflames.com/shots/scramble_mame_side.JPG
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