Pilot reported an electrical malfunction resulting in a precautionary landing. The landing was made at an airport with a closed tower and normally closed to civilian aircraft.

Narrative

While in route to ZZZ from ZZZ1 about 7 miles north east of ZZZ2 I was trying out the ADF and I began to smell what smelled like burning electronics. At this point my amp meter pegged out at 30 amps. I had already tried to get the ATIS the Class D and had heard that the Tower was closed for the weekend. At this point I turned off the ADF. The amp meter remained pegged and I still could smell hot electronics so I made a radio call that I was turning back towards ZZZ and then turned off the master. I looked around and saw what I thought was ZZZ3 and headed for it as it was the biggest airport in sight and most likely to have emergency services if I needed them. On short final I realized i was landing at ZZZ2 instead of ZZZ3. I turned the master back on and made a radio call. After landing I pulled off at the first taxi way and turned off the engine. I removed the ADF (which was all messed up); looked the plane over and added some oil. I then started the plane and did a run up. All was well. No bad smell and the amp meter was reading normally. I made my radio calls and then took off to continue on to ZZZ1. Later on I looked at the chart supplement for ZZZ2 and saw that it was closed to civilian aircraft. The ATIS said nothing about the airport being closed to civilian aircraft; Only that the Tower was closed.