Re: doppler question
That is an EXCELLENT question - and it comes up all the time during my presentations.
The "easy" answer: There's less of a Doppler shift on the VHF side than there is on the UHF side - so working the FM LEOs doesn't require a Doppler correction for the VHF side of things.
The "engineer's" answer: The formula for the frequency shift is df = - f * dr/dt / c where f is the transmitted frequency, and c is the speed of light, and dr/dt is the rate of change of distance vs time. The only thing to remember from this formula is that things are simply proportional. Proportional to f, and proportional to dr/dt.
A "layman's" explanation: Go to this page, and you'll be an expert in describing the Doppler phenomenon to all ...