Car radio (1994 Honda Civic LX) radio will not power on after jump start?

My 1994 Honda civic was sitting for quite some time and the battery died. The radio was in perfect working order before this. After the jump start the radio will not power on at all. I have checked the fuse under the steering wheel and the fuse attached to the head unit itself. I looked for faulty wiring on the converter and did not see anything. I even plugged a different stereo in to make sure it wasn't my actual stereo and that one did not work either. I did a google search and it seems like everyone was looking for codes? My radio isn't even turning on to ask for a code. Any suggestions?

Ohm the fuses. You can't always tell by looking at them. Using a voltmeter here helpful.

Check the fuse labeled "backup" in the fuse box under the hood (passenger side, near the firewall)