1994 Toyota Camry no dash lights, no click, good battery 13.6v

Bought a car today and it started right up. Took it
home. Didn't start. No dash lights, no click, no
nothing. So I checked the battery. Battery was
13.6v. Guy told me to jump it so I tried. Low and
behold turn the key and all the lights come on and
it starts right up. The time on the clock did not go
forward from the time I had last turned the car off
it was still 1:11, then after I started it the clock
turned to 1:12. Funny how I noticed that. Also I had
programmed the radio to have a radio station and
when I turned the car on again after jumping it the
radio station I had programmed was gone.

Then when I had the car off for 10 min after
jumping it started right up.

I'm assuming after I wait longer it wont start. I'll
post again later when I know.