NES Displays Wavy Lines

[wingzrow]

It's there for all games, and they are present even when there is no game inside the toaster.

Any idea what causes this?

Same problem on all tvs, same problem with multiple composite cords, and i'm using a name brand power cord so we can rule that out.

[APE992]

EMI from within the console probably. I'd take the whole thing apart (you'll need to spend quite some time desoldering the cage around the A/V+power box) and start by replacing capacitors. Give everything a good cleaning making sure to secure the shielding completely. If it has a gap somewhere it'll easily let something in from the outside world.

I'd also try plugging the power adapter into a circuit in your house that isn't connected to anything already plugged into it that has an electric motor (fridge, hair dryer, vacuum cleaner, fan), heating element (hair dryer, space heater), dimmer switches (these generate tons of electrical noise).

A battery would be a good idea to completely eliminate the possibility. The fact your adapter is "name brand" doesn't mean the transformer inside isn't generating EMI either.

[wingzrow]

Hmm, well that might make sense. Ile try plugging it into the wall but I DID remove a number of parts from this system while messing with years back. I was trying to better understand how to take the system apart when I was replacing the 72 pin connector. The only thing besides the connector that I changed was cutting pin 4 on the lockout chip, which I had heard helped games boot better. Something to do with the lockout chip actually blocking real games from working properly. I suspect I never put the shielding back in. Ile have to take a look at it.

[FABombjoy]

If you can hear a 60Hz hum in the audio then it's probably a bad power supply filter cap or two. I've had the exact same problem before and putting in a cap kit fixed it.

[APE992]

If you can hear a 60Hz hum in the audio then it's probably a bad power supply filter cap or two. I've had the exact same problem before and putting in a cap kit fixed it.

The main culprit I could think of in that is the very large 2200uF @ 25v capacitor that I'm pretty sure filters the power input on its way to the voltage regulator.

C21 - 2200uF 25v
C23 - 100uF 25v
C25 - 100uF 10v
C29 - 1uF 50v
C35 - 1uF 50v
C36 - 10uF 16v

The above is a list of all electrolytic capacitors on the A/V board.

[Yoder]

Yes, I recently picked up one with the same problem. Actually, the display looked great when I first bought it...for about one minute, then I got the wavy lines and I haven't seen a clean picture since.

I found a post on NA that seems to describe the same problem. The OP mentions changing a "power cap", but never gives more details :-/

http://www.nintendoage.com/forum/messageview.cfm?catid=8&threadid=42818

It does seem like a signal conditioning issue (when the power board converts AC to DC), from what I've read.

I suspect it's the huge cap on there, but who knows. Regardless, it looks like a pain to change.

[APE992]

Actually the big one is really easy to change. The bottom half of the shielding for the A/V+power comes off without any additional work, the top half requires a bunch of desoldering. Since the 2200uF cap sticks up through the top half of the shielding all you have to do is remove the solder from the bottom and it pulls right out and a replacement drops back in.

You do have to take the whole NES apart which isn't a big deal if you find the lines annoy enough.

I forgot to mention, those capacitor values are for MY NES, other NES systems may have different values.

[Yoder]

Ok, cool. Thank you. Yeah, I was wondering if it could be desoldered from the bottom, though. I already have the NES all apart. I saw some big caps at RS...I wonder if they have that one?

The wavy lines aren't terrible, but on a 47" LCD they're very noticeable.

[APE992]

They might but it would depend on if your RadioShack stocks a variety of capacitors. I found a spare 2200uF 25v cap in my component drawers, as a result I don't know how good it is but it seems to function.

[DashV]

They might but it would depend on if your RadioShack stocks a variety of capacitors. I found a spare 2200uF 25v cap in my component drawers, as a result I don't know how good it is but it seems to function.

I now have an NES with the same problem.

Did swapping that cap fix your issue?

[aphixe]

I'm curious myself, I have a spare nes to mess with. also how hard is the whole process i am not a soldiering expert at all I know the nes is relatively easy to take apart and such

[APE992]

I'm curious myself, I have a spare nes to mess with. also how hard is the whole process i am not a soldiering expert at all I know the nes is relatively easy to take apart and such

It's not hard to do but it's also not hard to screw it up and lift traces. Don't do it unless you've got some good practice in on desoldering through hole components.

[BetaWolf47]

I just ordered caps last week and have an NES with this issue that I am recapping for this very reason. I will post my results when I am finished.

[BetaWolf47]

Just recapped my entire NES, power circuit and all, and I can happily say that the wavy lines have been completely eliminated!