Restoration of Shielding and Buttons

[Tebroc]

Hello all!

 

I just recently acquired a 7800 from my step-brother, the one Atari console I've never owned till now! Sadly it did not work. After taking it apart, it quickly became a apparent as to why; it had some water/rust issues. To begin with, the shielding was rusted, particularly the part that comes in contact with the outer edge of the mother board. After removing the shielding from both sides of the motherboard, it was apparent that a good amount of corrosion had taken place, especially on the front of the board (power buttons, controller ports, etc.) I cleaned as much as could with 91% alcohol before bathing the front of the board (not the capacitor end) in white vinegar. I scrubbed the rusted area with an old soft toothbrush and rinsed it thoroughly with distilled water. After drying it on at a low temperature in the oven and waiting about 24 hours, I plugged in the power and AV with top off to find that it works (with a great deal of trouble with the power button.)

 

I searched the forums here and found mention of this part: Mouser.com

 

Just to be sure, is this the best recommendation? The other 3 are not working either so I want to do them all.

 

Also, though my continuity tests looked good and the console does function, I'd love to remove ALL of the rust stains on the PCB. Any advice there? I think my vinegar idea was probably not very beneficial.

 

And finally, I used a wire brush on a grinder to remove as much rust and corrosion from the heat shields, however, I'm concerned about putting them back in the system. I don't know what caused the rust to begin with. Perhaps water dripped into the system, I don't know. But is their a coating I should be putting it (like a clear coat?) It seems paint would be a bad idea. Any thoughts or suggestions? Also, is this a heat shield or an RF shield? I'm wanting to keep the integrity of the system and also to keep it running for years to come.

 

Thanks in advance!

[+Mitch]

From what I can tell by looking at the data sheet the mouser part you linked to appears to be the correct one.

 

The shielding is for RF protection, so you probably don't want to put a coating on it. Just nice shiny metal.

 

You could try DeoxIT to clean the board, though I've never tried it with really nasty stains.

 

Mitch

[jaybird3rd]

Hello all!

 

I just recently acquired a 7800 from my step-brother, the one Atari console I've never owned till now! Sadly it did not work. After taking it apart, it quickly became a apparent as to why; it had some water/rust issues. To begin with, the shielding was rusted, particularly the part that comes in contact with the outer edge of the mother board. After removing the shielding from both sides of the motherboard, it was apparent that a good amount of corrosion had taken place, especially on the front of the board (power buttons, controller ports, etc.) I cleaned as much as could with 91% alcohol before bathing the front of the board (not the capacitor end) in white vinegar. I scrubbed the rusted area with an old soft toothbrush and rinsed it thoroughly with distilled water. After drying it on at a low temperature in the oven and waiting about 24 hours, I plugged in the power and AV with top off to find that it works (with a great deal of trouble with the power button.)

 

I searched the forums here and found mention of this part: Mouser.com

 

Just to be sure, is this the best recommendation? The other 3 are not working either so I want to do them all.

 

Also, though my continuity tests looked good and the console does function, I'd love to remove ALL of the rust stains on the PCB. Any advice there? I think my vinegar idea was probably not very beneficial.

 

And finally, I used a wire brush on a grinder to remove as much rust and corrosion from the heat shields, however, I'm concerned about putting them back in the system. I don't know what caused the rust to begin with. Perhaps water dripped into the system, I don't know. But is their a coating I should be putting it (like a clear coat?) It seems paint would be a bad idea. Any thoughts or suggestions? Also, is this a heat shield or an RF shield? I'm wanting to keep the integrity of the system and also to keep it running for years to come.

 

Thanks in advance!

Welcome to AtariAge!

 

The switch you linked to is indeed the correct replacement part for the 7800; I've used several of them in my own consoles.

 

I had a similar experience with cleaning rust stains from a circuit board; in my case, it was inside a water-damaged Intellivision Computer Adaptor that I acquired from eBay. I wrote a bit in this post about the procedure I used to repair the damage, including some before and after pictures. Basically, I cleaned off the rust using a toothbrush and ordinary toothpaste, with a little help from Goo-Gone for the more stubborn residue.

 

If you decide to attempt something similar to repair your console, my best advice would be to make absolutely certain that the console is completely dry and that any residue left over from the cleaning process is removed before you plug it back in. I shook my board to get rid of as much excess water on the surface as I could, then I used some canned air to blast away any excess water under the larger components, and then I left it hanging in front of a fan for a few days.

 

As for the RF shielding, I actually have an extra 7800 RF shield that I could send you, which might be easier than trying to clean all the rust off of yours. Send me a PM if you're interested!

[Lendorien]

I replaced all of my switched with the mouser part mentioned above (it was my thread you got the link from), and they work great. As for as replacing them. I heated around the leads on the bottom with a desoldering iron, sucked out the solder and then soldered the new ones in. Very simple overall.

[mimo]

I run my 7800's,5200,8bit ataris, xbox etc with no rf shielding installed. No problems in the last 4 years

[Tebroc]

Thanks guys for all the help. I've ordered my parts from Mouser. I'm pretty excited to get this all sewn up! Thank you Jaybird for the offer on the RF shield. I might take you up on it. I'll see how I progress with bottom shielding (cleaning.) Lendorien, thanks for posting that info. I wouldn't have been able to find the part on my own. Man I wish the shipping wasn't so much from there Mitch and Preppie, thanks for the advice. If all goes well, I'll post my out come. I'm glad I found these forums. Very helpful!

[ApolloBoy]

I run my 7800's,5200,8bit ataris, xbox etc with no rf shielding installed. No problems in the last 4 years

Same over here. Just toss the RF shields, you don't need them.