9v AC went into my AV Famicom (HVC-101)

[DumbAndEmbarassed]

I picked up an AV Famicom today, and it came with a generic, tiny power adapter that gave off a feint, high-pitched whine when I plugged it in. Being very sensitive to these kinds of noises, I checked to see if I could use my OEM Nintendo power adapter. Both were 9v, both had the same barrel size, but it didn't occur to me to check DC vs AC.

So anyway, I powered on the unit long enough for my Framemeister and HD60 Pro to sync up and show no video with some alarming audio. Immediately powered it off and gave it a sniff, checking for the smell of ozone/electrical smell/magic smoke, which I did, but it wasn't too strong. Took the system apart, and it seems like all the smell is coming from the rear, possibly from the 5v regulator. I switched over to the power supply that came with my unit and measured 9-ish volts between I and G, and 5-ish volts between G and O, so it seems like the regulator is working? But the video is grey and the sound is, I don't exactly remember right now, but a light buzzing I think. There aren't exactly a lot of components on this board, so if the 7805 is okay, then that leaves a number of capacitors, so do I need to replace those? Should I be okay replacing the 7805 and the electrolytic caps or is there potentially more serious issues like fried CPU/PPU? Doing a visual inspection, nothing looks burnt or bulging. The only thing I've noticed is what looks like old brown flux residue around the through-holes for the 7805. Normally I wouldn't think much of it, but the rest of the board is completely clean with no other signs of flux residue. Might be coincidence? Never mind, I looked at it again and the 7805 is nowhere near the board, so nothing would have leaked out and made it to the other side of the board, which, in retrospect, how would it get to the bottom of the board anyway? It wouldn't. I'm just flustered.

I've done a fair bit of searching but haven't been able to find much, and what I have been able to find has been specific to the HVC-001 and similar RF Famicoms. Any help would be very much appreciated. 

Edit: Maybe HVC-101 isn't super specific. The model on the board says HVCN-CPU-01.
Edit 2: Finally found something relevant (it was the 120th search result, so it took a while to find). In this post, they describe the same issue, with a similar possible fix, but no resolution. Guess I'll order a 7805 and pray to Masayuki Uemura, though I would still be keen to hear what other people think may be wrong.
https://www.famicomworld.com/forum/index.php?topic=13671.msg177159#msg177159

Edit 3: It's really weird to me that the 7805 is outputting 4.8v but the system is still not working, which leads me to believe something else is messed up. I tried testing for voltage in other places. On the PPU I see 4.8v between pins 20 and 40, and I also see 4.8v on the PPU between pins 20 and 40.

[DumbAndEmbarassed]

Nevermind, I guess it was just being fussy (bad cartridge contact maybe?). But it seems to be working fine plugged into my TV, so... ¯\_(ツ)_/¯

[P]

Heh you were lucky. Or maybe AC isn't as devastating as wrong voltage is, I don't know. I'm glad it didn't kill it.

But yeah Famicom's are fussy with the cartridge connection. The edge-connector on most cartridges are not in the best shape anymore and the one in the console might also be aged. Probably doesn't help that Famicom cartridges wiggles around in the slot quite easily.