You would be using a radio if you were trying to tune into an AM or FM frequency.
a radio
Tune the piano's A440 to the fork. You don't have to tune it perfectly at first. As long as you know what side of "smooth" you're on, you can tune A440 so that there is a comfortable beat-rate when played with the fork. Then tune the piano's A220 to the piano's A440. Make the beat rate for A220 the same as when you play A440 against the fork. If you made A440 sharp, tune A220 "outside of smooth". If you made A440 flat, tune A220 "inside of smooth". A220 will be in tune. Alternative: Tune one wire of A3 with the fork, as described above (but tune it near the correct frequency). Then tune the other wires of A3 to the first one, using the same "beat" idea. Finish by pulling the first wire to unison.
Resonance
Your best bet would be to by a "pitch shifter" pedal. I wouldn't recommend trying to tune it up an octave.
Light pressure low frequency, press down to rest diaphragm against inner ridge for high frequency
The Band
A radio?
...A radio...
radio radio
A radio?
You would probably be using a radio receiver. It is possible you'd be using a transceiver, which combines the functions of a transmitter and a receiver.
a radio
To change the frequency of a guitar string, you would adjust the tension on the string by turning the tuning pegs. Tightening the string increases the frequency, while loosening it decreases the frequency. Tune the string to the desired pitch using a guitar tuner or by ear.
The beat frequency of two in-tune musical instruments is zero.
The tune of What's the Frequency Kennith appears on REM's Monster cd. The song was written by Bill Berry.
tune to the frequency
The beat frequency of two in-tune Musical Instruments is zero.