Finally fixing my NES

[NES Fan]

Alright, I’ve had problems with my NES off and on for years now. But I only chalked it up to its age. I’m not teck-savvy, so I though I couldn’t do anything about it, just keep cleaning the cartages until it worked. I just bought two new games, Kirby and Castlevania. They are incredibly fun. It kind of bothered me that I had to clean these games every time I wanted to play them. So I scoured the internet, and surprise-surprise the internet is a wealth of knowledge (sarcasm). It turns out, I guess the NES was built like a tank, some different kind of way they attached everything together, and it was manly two things screwing everything up. The 72 pin connecter and the CIC chip.

My NES suffers from the blue screen, and the constant resetting (the blinking red light). So, with this new knowledge I decided to do the following (basically a combo of everything I read). I’ll of course dismantle my precious NES, and get access to the pin connector and the motherboard. I’ll clean the metal contacts on the motherboard with Brasso metal polish, and try to re-bend the 72 pin connecter (not really looking forward to that). Then I’m disabling the CIC lock-out chip, which I guess is the culprit behind the resetting problem. Because the CIC chip in the NES can’t detect the CIC chip in the cartridge, probably due to a bad connection. So after all of that the NES should work as if it was new right from the factory. I’m also cleaning the plastic shell, it yellowed and it’ll be nice if it’s actually gray. I’ll be doing this tomorrow, and I’m planning on filming a tutorial on this. So wish me luck.

[NES Fan]

Alright, I got some good news and some bad news. First, the good news – I managed to dismantle it without a problem, and I got the CIC chip disabled. Now for the bad news – I pretty much ruined my 72 pin connector, I just finally bought a replacement. So in a week or so I should be back in business and fix this thing once and for all.

[RedWolf]

Good luck!  Believe it or not, I actually wrote about this issue on VC&G back in 2005:

http://www.vintagecomputing.com/index.php/archives/13

Almost five years ago.  Man, how time flies.

[NES Fan]

Thanks for that. I bought my replacement over at dkoldies.com. What do you think of that site, like if it's reputable? I've bought items from there before, but I haven't bought something this important before. Any help will be appreciated.

[RedWolf]

I'm not sure if it's reputable, but I personally wouldn't buy stuff from there.  Their 72-pin price ($9.89) isn't too bad, I suppose.  Just take a shot and see what happens.

[NES Fan]

Alright, I’ll try to explain this to the best of my ability.

This is the strangest thing, I swear. Well I got the new 72 pin connector and got everything put back together. Now it plays games perfectly, I pop one in there and it plays flawlessly. But I can only play a game if I don’t push the game caddy down. This is odd, it works perfectly, but it shouldn’t work like that. I double-checked my work several times. I had the 72 pin connecter aligned correctly, I disabled the CIC chip correctly, and I didn’t break any of the electronics on the motherboard. I simply have no idea. Any help on this matter would greatly be appreciated.

[sirpaul484]

I noticed the exact same thing when I replaced the 72-pin connector on my NES.  I never figured out why.  I just pretty much shrugged my shoulders and breathed a sigh of relief that it at least worked.

[RedWolf]

Alright, I’ll try to explain this to the best of my ability.

This is the strangest thing, I swear. Well I got the new 72 pin connector and got everything put back together. Now it plays games perfectly, I pop one in there and it plays flawlessly. But I can only play a game if I don’t push the game caddy down. This is odd, it works perfectly, but it shouldn’t work like that. I double-checked my work several times. I had the 72 pin connecter aligned correctly, I disabled the CIC chip correctly, and I didn’t break any of the electronics on the motherboard. I simply have no idea. Any help on this matter would greatly be appreciated.

I know exactly why this is happening.  I'll quote my article from 2005 I already mentioned, then try to explain more:

The crux of this classical problem is a special connector inside the unit that wears out from repeated usage over the years. It was designed in such a way that a game cartridge can be inserted at a slight angle with little resistance, then pushed down in the spring-and-latch loading tray inside the NES, bringing the cartridge’s contacts in full contact with the connector’s pins. It’s sort of like a cartridge port version of a ZIF (zero insertion force) socket.  This mechanism seems like a great idea on paper — there’s no brute-forcing the game in, and it’s easy to pull the game out of the slot when you’re done. But this delicate dance between cartridge and machine repeats it self over and over again throughout the years until the the pins in the internal connector start to lose their flexibility and springiness. And when they get slowly bent down from repeated usage, the physical contact made between the connector and the cartridge itself suffers, making it hard for the NES to read the data on the cartridge.

The original NES 72-pin connector was special.  It was designed so you could insert a cartridge with very little force, then "seat" the cartridge's contacts in the 72-pin connector by pushing the NES cartridge holder mechanism down.  In pushing it down, it pushes the cartridge contacts into the right place to make contact.

The new 72-pin connectors do not have this feature.  Every one I've seen has a simple right-angle connector for the game cartridge socket.  That's the same sort of connector you'd find in the top-loading NES: you stick in the cartridge and it requires some force to seat it in place. Friction on the contacts holds the cartridge in the connector.  If you wiggle the cartridge front to back, you'd mess up the cartridge's contact with the pins inside the connector.

The same thing is happening in your refurbished NES.  Since it no longer has the special zero insertion force connector (that worked when the cartridge was pushed down in the mechanism), you need to treat it like a regular 'ole friction connector that needs the cartridge contacts perfectly parallel to the connector opening to work properly.  Some of the knockoff 72-pin connectors can handle the angle introduced when pushing the cartridge down (mine can), but I'm sure it wears those connectors out faster.

Got it?  If you need me to clarify anything, let me know.  You should examine your old 72-pin connector to see what I'm saying about it.

[NES Fan]

Like I said before I didn't know much about these older game consoles. I threw mine away before getting a chance to examine the two together, I tore the crap out of the pins on my original with trying to fix it my self. Anyway, thanks for the info. It's actually greatly appreciated, I had no idea what was going on. I guess I didn't screw anything up, that is really good to know. Again thanks.   

[orsty3001]

When you replace it with one of these knock off 72 pin connectors, just get one of those retrousb carts. Dump all the NES roms a cf card for it and just plug it in once.

Then never remove it.

Ever

[RedWolf]

When you replace it with one of these knock off 72 pin connectors, just get one of those retrousb carts. Dump all the NES roms a cf card for it and just plug it in once.

Then never remove it.

Ever

That's exactly what I did.  My NES cartridges have been in a box in the garage since I bought the NES PowerPak.

[orsty3001]

That's exactly what I did.  My NES cartridges have been in a box in the garage since I bought the NES PowerPak.

Nintendo built a hell of a product. Most of my old games still work but there are limits in the materials they used. There is just no getting around wear and tear.

I had a Game Boy game that fell out of a box in storage and sat on the floor for years. It saw rain, where some came under the door, dirt and whatever else mother nature could throw at it. I picked it up not too long ago and tried it in my Super Game Boy. It didn't work the first time but I took it apart and cleaned up the connectors with 1500 grit sand paper. Works a treat now.

It's amazing the data retention these old carts have and in most cases how easy it is to get them working again even after abuse.

[RedWolf]

I had a Game Boy game that fell out of a box in storage and sat on the floor for years. It saw rain, where some came under the door, dirt and whatever else mother nature could throw at it. I picked it up not too long ago and tried it in my Super Game Boy. It didn't work the first time but I took it apart and cleaned up the connectors with 1500 grit sand paper. Works a treat now.

It's amazing the data retention these old carts have and in most cases how easy it is to get them working again even after abuse.

The mask ROMs inside the cartridges should last indefinitely -- hundreds of years or longer barring extreme environmental stresses.  The data is permanently etched into a piece of silicon inside a plastic package.

The trick is getting all the supporting circuitry to last that long as well (especially in the video game system itself).   In particular, resistors and capacitors change value over time and need to be replaced.  Capacitors leak and wear out, and I've had to replace many in equipment that's no more than 20 years old.

[Zachary]

Yeah, too bad they stopped making video games and computer software on cartridges - they're a lot more durable than CD-ROMs, tapes, or floppy disks.

[sirpaul484]

Yeah, too bad they stopped making video games and computer software on cartridges.

Actually, I like to consider memory cards, namely the CompactFlash card (and to some extent the SecureDigital card), to be the next logical evolution of the cartridge, but I think I'm starting to get off topic here.