Glitchy sprites on FDS

[Zycrow]

Hey there folks. I got my hands on a FDS today that almost works 100%. The problem is that in all of the games, the sprites show flickery glitchy areas, some worse than others.

Here's a pic of what happens to Mario on SMB2, if you can tell:



I also have Metroid, Doki Doki Panic, Baseball, and Moero Twin Bee, and similar issues are present to various degrees on those games.

The former owner of this FDS says he has used it as his personal system, with no issues, for the past four years and I am inclined to believe him; I think the problem lies somewhere in the connection between the FDS and my Famicom. Here are things I have done so far:

- Tested the Famicom with regular cartridge games, just to be sure (they work fine)
- Cleaned the RAM adaptor's pins with brasso/alcohol.
- Cleaned the Famicom's pins using both a game swabbed with brasso and with a t-shirt/credit card combo and alcohol.

After a few rounds of pin-cleaning, the glitchiness was still present.

As a final note, my Famicom is one of the ones that was restored and given AV modification in Japan. Hopefully this is not the issue. Here's a pic of my setup, just for reference sake:



I'm not sure what else I can do. Does anyone have any suggestions? 

[Raverrevolution]

I remember reading posts a long while ago on the same problem and I believe it had to do with the memory chips in the ram adapter.  Some of them would go bad and you just had to unsolder them and replace them.

Someone else has to chime in with specifics or do some research on that to find the thread.

Here's one of the many threads;
http://www.famicomworld.com/forum/index.php?topic=9232.0

[P]

Here's the thread you were looking for http://www.famicomworld.com/forum/index.php?topic=8512.0.

[Zycrow]

Thanks - I did actually find those threads shortly after I posted this, so later when I get home I'll see if I can open my RAM adapter and check what chip I've got in there.

However, I'm not exactly clear based on those threads on what I would need to do to fix it. Buy a new RAM adapter and hope it's got a better chip? Find a replacement chip and learn how to solder so I can put a new one in?  

Edit: I see this now:

Some of them would go bad and you just had to unsolder them and replace them.

If that's the case, where would I go to find a new one?

[zmaster18]

I still don't believe it is the RAM adapter, because I never had this problem once when I used this system all these years.  The last time I used the system was 2 weeks ago, I don't see how the RAM adapter would suddenly go bad that quick. I still think you need to scrape the surface of the pins in the cartridge connector with a metal file, it works like a charm for me! Although Brasso is great for making the surface of the contacts clean, you may have to get underneath the surface of the pins if the surfaces are a little dull or corroded.

[Zycrow]

I still don't believe it is the RAM adapter, because I never had this problem once when I used this system all these years.  The last time I used the system was 2 weeks ago, I don't see how the RAM adapter would suddenly go bad that quick. I still think you need to scrape the surface of the pins in the cartridge connector with a metal file, it works like a charm for me! Although Brasso is great for making the surface of the contacts clean, you may have to get underneath the surface of the pins if the surfaces are a little dull or corroded.

That's the next thing I'll probably do - do you know of any reference videos or pics of this process online? I'm sure it's simple but I'm nevertheless wary to approach my old game systems with abrasive metal. 

[zmaster18]

It sounds a bit scary and destructive, but it's just a couple little scratches. If you do it, you will have a solid connection. Like I said on ebay, if you have a game in the slot and wiggle it while the power is on, the game won't crash and still runs! I run a metal file 2 or 3 times gently up and down in the cartridge slot in the systems, and then for games you can rub the metal file across the connectors gently and blow out the dust after, and voila!  The games are like brand new because the metal is now exposed without any dull layers preventing bad connection. You don't need to use much force, be gentle and any corrosion comes right off and you have the shiniest pins possible. You can finish with brasso for a smooth finish if you'd like!  Try it out if anyone reading this has a metal file. You can bump, bend, or wiggle the cartridge while the system is on and it will never crash!

[P]

Yeah well cleaning the contacts should be the first thing you rule out. Don't use anything but alcohol. 99% Isopropyl alcohol is usually recommended. For polishing the RAM adapter's pins you probably need a fiberglass brush to be able to reach them. That worked for me anyway, and my games doesn't crash anymore even if wiggling the RAM adapter.

The thing with the RAM chips is that some probably has a manufacture flaw which makes them degrade over time. This may not be immediately noticeable. I can't help you where to find compatible RAM chips though. However I can say that soldering and desoldering chips is not a good beginners soldering project.

Do you have FDS Pro Wrestling available? If so does it have graphical glitches?

[Zycrow]

Yeah well cleaning the contacts should be the first thing you rule out. Don't use anything but alcohol. 99% Isopropyl alcohol is usually recommended. For polishing the RAM adapter's pins you probably need a fiberglass brush to be able to reach them. That worked for me anyway, and my games doesn't crash anymore even if wiggling the RAM adapter.

The thing with the RAM chips is that some probably has a manufacture flaw which makes them degrade over time. This may not be immediately noticeable. I can't help you where to find compatible RAM chips though. However I can say that soldering and desoldering chips is not a good beginners soldering project.

Do you have FDS Pro Wrestling available? If so does it have graphical glitches?

I have cleaned the connectors on the RAM at least once and in the Famicom several times.

I don't have Pro Wrestling, just the games mentioned above (SMB2 with Baseball on side B, Doki Doki Panic, Twin Bee, Metroid).
Post Merge: April 26, 2014, 09:08:04 am
All right, here's what I've done since my last post:

- Opened up the RAM adaptor to inspect its innards. It does not appear to have the type of chip that causes graphical glitches, although I'm not 100% certain on this.
- Cleaned the RAM adaptor's pins (again) with alcohol.
- Filed the Famicom's connector pins.
- Filed the RAM adaptor's connector pins.

Same result.

[P]

Those faulty chips are still a big mystery. I would suggest to ask at a more technical forum about chips. The people at nesdev are often using ram chips and there's lots of technically knowledgable people there.

Do you have any way of testing the FDS on another Famicom? Then we could at least rule out your main unit.

[Zycrow]

Those faulty chips are still a big mystery. I would suggest to ask at a more technical forum about chips. The people at nesdev are often using ram chips and there's lots of technically knowledgable people there.

Do you have any way of testing the FDS on another Famicom? Then we could at least rule out your main unit.

I do have a second Famicom, but it is inoperable (pretty sure I used the wrong type of AC adaptor a few years back). Too bad I can't jam the RAM adaptor into my American NES. 

I'll snoop around at nesdev and see if I can get some help there.

(At any rate I'm glad that the system is completely playable. In the case of Doki Doki Panic the garbling is almost totally unnoticeable. It's the worst in SMB2 where half of Mario's sprite is garbled.)

[fredJ]

Of all my at least 20 RAM adapters, all but one have worked...
Sometimes people on forums make a big deal and being too inventive that chips will go bad , etc, but I am not aware of any chips for any system that automatically degrades with age. Capacitor, yes (and maybe EEPROMs etc). 
Not saying chips can't go bad sometimes.

Since you have had the problem with your famicom since day 1, why think of complicated solutions... Most likely it is something with the famicom.
The FDS + Ram adapter is more complex than a regular cart. It could be something with the timing function/mechanism, which I have some recollection is special on the FDS technically. It may also use different pins than a regular cart so there may be a problem there.

Or, I could be completely wrong. But simplest and cheapest may be to buy an unmodded console and test it with the RAM adapter. Even if you get a bad picture, you'll probably get a picture good enough to tell if it has the ghosting.

[P]

Yes I agree that it's best to test it with another Famicom and rule out all other problems before starting to replace chips and such. People often tend to suspect complicated problems like a faulty PPU or CPU even though the most common problem is just dirty or oxidated pins.

[Zycrow]

Hey there folks. I wanted to update this thread for the purposes of other people having this problem in the future. I took my issue over to NesDev, and we had a lengthy discussion and one of the members even mailed me some of his components so I could mix/match and see what happened. The results were pretty strange. Here's the thread:

http://forums.nesdev.com/viewtopic.php?f=10&t=11202&p=128248#p128248

If you don't feel like reading through all that, here's the short version: Some RAM adapters work with my modded FC, and some don't. When I purchased a second FC (non-modded), the RAM adapter that zmaster sold me worked perfectly on it.

[zmaster18]

Ah, great to see that the problem was finally resolved after all this time! It's weird how it didn't work on a modded Famicom. However, my Fami is AV-modded and never had a problem with it.