All,

I have a Toaster NES hooked up via composite to an older 32" Sharp 720p LCD.  When using my NES Powerpak, I get wavy lines on the screen.  None of my other carts produce these wavy lines though.

Anyone have any ideas of what could be causing the Powerpak to do so?  Is it some sort of interference caused by the Powerpak?  Any other thoughts?

Thanks

Updated OP with pictures.

PIC1:  Powerpak playing SMB.  These lines wave back and forth and go up and down the screen.

PIC2:  Vs SMB cart from retrozone.  Notice, no wavy lines.

I don't have a powerpak, so I can't say much about that, but it looks like you are getting some video interference. Do you have another NES to try it out on? One thought would be if your NES is missing the metal shielding from inside.

Also, try other inputs on your TV if you have them.

The shielding is there on the inside and I've tried 3 different inputs.

I'll be trying a different TV/monitor later tonight and I am going to borrow a buddies NES and Powerpak tomorrow and try different combinations.

Any other ideas?

Tried 3 other TVs and the wavy lines still existed. I will be trying a different NES powerbrick tonight to see if it is a power issue.

Oh wow, I didn't even think of that. Yeah, if your power adapter is crappy or non OEM, that could cause all types of unwanted problems. At this point I would put money on the power adapter solving the issue.

My Power adapter is official, but it's 25+ years old. All games work fine, but the powerpak stuff. I just wonder if it doesn't have enough "unf" left to provide the powerpak with enough juice.

Try using a CRT TV.

Almost certainly not the issue.

Thanks though.

FYI.. to all who are interested. Brian says it is "almost certainly" a power supply problem. I'll be testing with a buddies AC tomorrow and will post results.

Thanks

^What were the results?

It was a bad power cap in the NES.

So a new power supply fixed the issue?

^ a new cap with the same values should work. Im gonna give it a shot on the next board I see with these bothersome lines. They aggrevate the crap outta me.

Hi, sorry for bumping into this old thread but I need to ask, especially ckendal and custom nes guy. Did replacing the cap 2200 uF/25V fix the problem? I have the exact same problem but with ALL my games.

I second bump this as i just ran into this problem myself for the first time. 

Could be a few things that cause the lines. Power adapter, internal parts in the NES, crappy video cable... I get real bad interference when I have my NES plugged into the same outlet as my PC, so also try a different outlet if you can. Just don't use an extension cord that can also cause a lot of interference.

I just ran into this problem myself and have been looking all over for a solution :-). It just happened randomly the other day. I replaced the AC adapter, Power switch, 72 pin connector. I did notice that Connecting the +/- on the Main board with a piece of metal makes it go away. But soldering the two together do not work, it has to be touched with a piece of metal at a certain angle for it to work, and the wavy lines disappear..Before I replaced the power button I ripped it out with a pair of pliers, and used a dremel to file down the White plastic parts to expose more of the Leads, and was able to put a screw between these two leads, and the wavy lines went away completely, I assumed it was the power switch so I replaced it and have the same issues...

I will try and replace a capacitor as well

I believe that I read somewhere (here on this forum most likely) that if you replace the AC adapter with one that Outputs DC (instead of the orignal NES one that outputs AC) then it will resolve this issue instead of replacing the capacitor. Anyone know for certain?

I'd say no, as you are just bypassing the rectifier basically and charging the capacitor with DC, which probably won't affect it much honestly. You can try it, though?

i tried using a Genesis 1 power adapter which is 9v DC and it did the same thing, also tried a different NES AC adapter same thing happened. The only time the Wavy lines dissapeared was when i touched the Positive and Negative on either the Mainboard, or power switch leads +/- with a piece of metal.

I have fixed the wavy line issues. I replaced the AV module on the NES. It has something to do with that thing because once replaced with a different one it went away.