Hello all, I am wondering if any of you could shine some light on the
formula the Regency HR-220 uses to determine the frequency of the RX
crystals?

A fellow ham gave me a Regency 220 Xtal rig and I have a few hundred
crystals but I do not have any documentation on this rig. Any assistance
would be greatly appreciated!

TIA.

Jim.. kb6zop
IRLP 3129
EchoIRLP 214691