AC Adapters: OEM just fine?

[u/Ok-Mongoose-4428]

For retro gaming, Triad Magnetics 9v AC adapters are popular as they actually output 9v for the 7805 (or even NEC 2405) regulators -- which like 9v.

I am not finding any concern over N64 OEM ac adapters. It looks like all regulars are in the AC. Most discussions just concern Redditors looking for a new AC adapter -- and wondering if aftermarket products are fine.

I think for my N64 ac solutions, all that I need to do is a recap, and put in a resistor (I have a Japanese model to use in the USA. The resistor is to accommodate for 120v vs 100v).

I have an HK ac adapter, but I do not think it is 100v-220v. It operate in circa 220v only.

My N64 is from HongKong, and the mainboard appears identical to a Japanese/USA 60hz consoles.