Thanks everyone.
I WILL get a voltmeter and check the battery under load before every flight!
I WILL observe the three flight rule.
I am going to do an extended radio check with the engine running with my new receiver and if I find any problems I am definitely moving to 2.4 ghz.
Crashing 2 planes in a row when I know it wasn't something I did on the sticks is very frustrating and I will do everything I can to make sure it doesn't happen again.
Good flying all.