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I Removed the RF Shield from My Astrocade Today

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It was surprisingly simple to do. The Astrocade Service Manual has good step by step instructions. (The only thing that's a little unclear is that in Step 8, you need to slide the keyboard toward the base of the keypad/cassette assembly.)

 

This Astrocade was working beautifully (I have two), but I hadn't played with it for a few months. It developed graphical glitches on the menu screen and during gameplay. I figured that even if the problems had to do with fried components, I ought to remove the RF shield anyway.

 

The unit worked great after the procedure but then reverted to its glitchy ways the next time around. I discovered that if I could get the menu screen to display without glitches, I could play for as long as I wanted to without any problems. I ran the Checkmate test for about 45 minutes, then played Galactic Invasion and Incredible Wizard for about 20 minutes, no problems. But the next time I turned on the Astrocade, I might get the glitchy menu or just a black screen. I have to try several times before I can get a "good," stable menu. So now I'm wondering if there is a problem with the power switch.

 

Anyway, I noticed that one of the the socketed ICs has a weird protruding pin. However, the pin isn't loose; it seems to be connected to the socket with a wire. The Astrocade FAQ mentions this (section 12e), which makes me wonder if this is the original IC or a copy. This is the "Custom Address" IC.

 

Just for fun, the third photo shows the "Custom Data" IC. That white stuff is thermal paste that had separated a long time ago from the heat sink on the RF shield.

 

If anyone has any thoughts about that ICs or the display glitchiness, I'd appreciate it. For everyone else with an Astrocade--this procedure is easier than you think it is.

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Pull the custom data chip and clean that paste off! It could definately be causing issues, since without the heat-sink on top the paste is just going to help keep the heat in. (Not like the 'cades heatsink was doing a great job to begin with).

 

See if it makes any difference and post an update.

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Pull the custom data chip and clean that paste off! It could definately be causing issues, since without the heat-sink on top the paste is just going to help keep the heat in. (Not like the 'cades heatsink was doing a great job to begin with).

 

See if it makes any difference and post an update.

 

I was wondering about the paste. I don't have a chip puller -- is there a trick to remove the IC without one? I'm going to use the isopropyl + coffee filter method to clean off the paste.

 

I'm beginning to think that the glitchiness has to do with the unit needing to "warm up." If I turn on the unit and get the glitches, I just wait a couple of minutes and hit "Reset." Everything works normally then.

Edited by boxpressed

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gently push a flat screwdriver between the socket and ic on the sides without the pins. Lift it a little, and then put the screwdriver on the other side of the ic and lift it a little again. Repeate moving from side to side, lifting little by little until the ic is out of the socket.

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Believe it or not, carb cleaner just plain dissolves thermal paste, old or new, much better than isopropyl alcohol. I know it sounds crazy, but trust me, it works. Just rinse the chip off with cool water afterwards and let it completely dry before re-inserting it.

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gently push a flat screwdriver between the socket and ic on the sides without the pins. Lift it a little, and then put the screwdriver on the other side of the ic and lift it a little again. Repeate moving from side to side, lifting little by little until the ic is out of the socket.

 

There's a small metal box between the Custom Data IC and the Cassette Connector that makes it difficult to get a screwdriver in on one side, so I haven't done this yet. The box seems to be soldered to the mainboard.

 

As you guys probably know, the Custom Data IC gets really hot. If I can remove it, I would love to put a proper heatsink on it. Do you leave it bare?

 

Believe it or not, carb cleaner just plain dissolves thermal paste, old or new, much better than isopropyl alcohol. I know it sounds crazy, but trust me, it works. Just rinse the chip off with cool water afterwards and let it completely dry before re-inserting it.

 

I used isopropyl alcohol, q-tips, then a coffee filter. I guess the coffee filter method is overkill if you're not going to install another heatsink. The IC looks pretty clean now, although I can see a couple of specks of paste in between the pins. I won't be able to remove them without removing the IC, which is presenting some problems (see above).

 

This morning, the unit booted up with a garbled screen, but again, after a few minutes and a few depressions of the "Reset" key, I got a "good" menu. The unit runs normally, as expected. If the unit runs normally at this point, am I doing any damage to the components?

 

Also, I'm assuming that you do not remove the cardboard stencil between the mainboard and the bottom metal tray.

Edited by boxpressed

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There's a small metal box between the Custom Data IC and the Cassette Connector that makes it difficult to get a screwdriver in on one side, so I haven't done this yet. The box seems to be soldered to the mainboard.

As you guys probably know, the Custom Data IC gets really hot. If I can remove it, I would love to put a proper heatsink on it. Do you leave it bare?

 

I use one of those small precision screwdrivers from a Radio Shack set to pry it up, it works just fine even with that box in the way. I know there have been articles on putting real heat sinks on the chip, but I never have since I remove the RF shield completely from the motherboard and always make sure the console in on a flat surface (I usually just grab one of those really large hardcover children's books from my kids and place the 'cade on top of it on the floor).

 

I used isopropyl alcohol, q-tips, then a coffee filter. I guess the coffee filter method is overkill if you're not going to install another heatsink. The IC looks pretty clean now, although I can see a couple of specks of paste in between the pins. I won't be able to remove them without removing the IC, which is presenting some problems (see above).

 

This morning, the unit booted up with a garbled screen, but again, after a few minutes and a few depressions of the "Reset" key, I got a "good" menu. The unit runs normally, as expected. If the unit runs normally at this point, am I doing any damage to the components?

 

Also, I'm assuming that you do not remove the cardboard stencil between the mainboard and the bottom metal tray.

 

The chip could still be flakey if it’s already been damaged, so it might always just be hit or miss with this console (unless you replace the chip). On your last statement, about the cardboard, I am not clear on what you are referring to. Pic please?

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I think I'll hold off on removing the CD IC, unless you think doing so is absolutely essential, Michael. I don't think a couple of specks of thermal paste behind the pins are causing the problems I'm describing.

 

Here's a couple of photos. The first one is of the bottom tray with the cardboard stencil.

 

The second one is of my OTHER Astrocade, which I think is an Astrovision model (there's no sticker underneath). I haven't removed the RF shield from this one because it looks more complicated. The Astrovision RF shield is now about half the size of the Bally RF shield, and it looks like there is some kind of jury-rigged heat sink for the CD IC.

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OK, now I see what you were referring to. I don't replace any of the RF shield at all, I re-install only the motherboard when I put it back inside the case. The RF shield serves no known purpose anymore, and since it was an afterthought anyway it’s not needed at all as far as being a structural piece for the console.

 

As far as the other picture goes, there are a lot of variations of the RF shield; many are shown on the Yahoo Bally Alley group page. I have probably come across almost all of them (save the plastic/aluminum coated one from the Home Library Computer) and all of them can be removed, trust me. And that heat sink is still pretty lame ass and probably not doing a whole lot for the chip anyway.

 

The fact that the RF shield is covering just about everything it possibly could that’s going to get hot is more detrimental to the motherboard than any benefit that metal bar is going to give.

 

You can keep the shield for its "originality" should you ever want to restore it, I just put it and any clips (some have them, some don't (I think)) in a zip lock and label which console it came from (or put it in the box for that console, if it had one).

 

Just take your time when you remove it. :D

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I'll get rid of the bottom metal tray as well then! I think I'll see how it goes with the Bally model before I mess around with the Astrovision's RF shield. I did swap out the power supplies, though, and it seems as though the Astrovision PS doesn't get as hot as the Bally's. Who knows, though!

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I keep my astrocade sitting on a laptop cooler, and it stays way cooler. And by the way, my video picture is clearer with the shielding still in place for some reason...

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I keep my astrocade sitting on a laptop cooler, and it stays way cooler. And by the way, my video picture is clearer with the shielding still in place for some reason...

 

So you've removed the shield and then replaced it?

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Those precision screwdrivers are terrible! The only thing they're capable of screwing is your hands. They've got less torque than a breadstick.

 

Anyway, I'll be trying to replace the micro USB port from a Windows phone in a couple of days, and I've been told that the best way to take tiny components from a printed circuit board is to set some desoldering braid on the components, then heat it. The braid draws out the solder, making chips easier to remove. I've tried a solder sucker, but it doesn't seem to pull the solder from tiny parts very well... even flicking the board from the other side seems to work better.

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