N64 Video Problems

[MagExp]

I bought a used N64 almost a year ago, and I've been noticing some strange things that happen when the screen goes black (or is very dark in the case of Doom 64) during gameplay. Whenever either of those cases occur, the video feed cuts out for about half a second and displays static before returning to normal. An example of when this occurs is the pre-mission images of single player maps in Goldeneye: as soon as the screen goes black, I get that static screen. With Doom 64, it's even worse, as it happens all the time due to the game's dark environments. I tried replacing the A/V cable, but that had no effect whatsoever. What I have found is that the game cartridge and the area where the power supply plugs into the console heat up pretty badly even after ten or so minutes of use, although I don't know if this is a common problem with the N64 or not. Hopefully I have provided enough info to give you an idea of what is going on, but this is an issue I have never heard of happening before.

[Niku-Sama]

I've come across heat like that before in computers and it was a bad solder join creating resistance, causes it to heat up enough to cause enough resistance that what ever on the other side wasn't getting enough juice and would cut out. probably cools off enough after to reconnect and continue.

could just be a bad power supply too, might be caused internally in the PSU and you feel it most closest to the plug on it because that's where the heat transfer is going to go (kinda like a heatsink on a computer)

i'd hunt down a N64 power supply replacement and see how that goes, should be able to find tons of them, people don't know what they are after they get separated from the system, then they get donated by them selves. I always pick em up for about a buck or so

[Guust]

"Displays static before returning to normal", so I assume you are using the RF modulator? That could narrow down the problem somewhere in the power line between the N64 and modulator. An RF-modulator without a video input signal would still produce a clean carrier, instead or dropping out.
Or does your TV automatically change to RF input (showing static) as soon as a composite/RGB input signal drops?

In addition to Niku-Sama: If you have a can of Freeze Spray (i.e. Kontakt 75), try spraying a bit on the suspected area(s) of the circuit board. If the problem disappears or changes, a bad solder joint is likely to be the cause.
Else try to cool the area using a hair dryer (cold air setting). Not sure whether it will work, it's worth a shot.

[MagExp]

I've come across heat like that before in computers and it was a bad solder join creating resistance, causes it to heat up enough to cause enough resistance that what ever on the other side wasn't getting enough juice and would cut out. probably cools off enough after to reconnect and continue.

could just be a bad power supply too, might be caused internally in the PSU and you feel it most closest to the plug on it because that's where the heat transfer is going to go (kinda like a heatsink on a computer)

That's funny, a friend told me the same two things just today. He said he had a power supply sitting around somewhere that he would happily give to me.

I am considering opening up the console, but I don't know what I would be looking for and changing the power supply might be the real problem. Do you know which part of the PCB I should look at to determine if there is an internal problem?

"Displays static before returning to normal", so I assume you are using the RF modulator? That could narrow down the problem somewhere in the power line between the N64 and modulator. An RF-modulator without a video input signal would still produce a clean carrier, instead or dropping out.
Or does your TV automatically change to RF input (showing static) as soon as a composite/RGB input signal drops?

I am using a generic Red-Yellow-White cable that also works with the SNES (the exact name of that type of plug-in escapes me at the moment). I replaced it once already and that did not do anything helpful. My TV does not experience problems like this with other composite plug-ins, either.

[Polygon]

That's funny, a friend told me the same two things just today. He said he had a power supply sitting around somewhere that he would happily give to me.

I am considering opening up the console, but I don't know what I would be looking for and changing the power supply might be the real problem. Do you know which part of the PCB I should look at to determine if there is an internal problem?

I am using a generic Red-Yellow-White cable that also works with the SNES (the exact name of that type of plug-in escapes me at the moment). I replaced it once already and that did not do anything helpful. My TV does not experience problems like this with other composite plug-ins, either.

If you open it I would look for corrosion anywhere on the board, examine the traces, and examine the capacitors and any other components on the system. Even the slightest bulge on a capacitor can cause a problem. Granted, there aren't always visual cues and could be tough to track down. As for your cables, were the other cables also generic or were they Nintendo brand? I ask because I've seen a lot of odd issues with 3rd party cables on N64s. I'd suggest trying an OEM cable as well.

[APE992]

If you can get ahold of a second power supply do so. If the supply is failing it can easily introduce noise into the power that otherwise is being filtered out; I've seen it before. If you can't find one I have plenty I can sell for a decent price. Cracking that thing open isn't fun.

As for the capacitors inside the thing I've not yet seen any bad caps in a N64, that's not to say that it couldn't happen but in the 100+ I've opened not a one has had an obvious capacitor problem. I'm not sure 3rd party cables would be a problem either but if the grounding went bad, or they weren't properly shielded you could have interference be induced in the cables if they were near a source of EMI.