That's a UHF MPI, a pretty basic radio and only about 2 watts output but still useable.
There should be a small switch on one side which selects another channel, it's been so long since I've worked on one that I don't remember which side but you'll see it if you look closely.
I'd bet the real tx frequency is 468.9875 MHz, you are probably picking a multiple of the TX oscillator.
I haven't played with the old xtal MPI's in years but as I remember the multiple is something like 8 times the tx xtal frequency.
If you need to get to the battery, simply press in on the the bottom front of the radio and the battery should come out for replacement
Mike