Hi Wayne...Are you referring to the Epson programmable oscillator chips? You can order them to put out a square wave on any freq up to about 125 mc as I recall. $4.10 apiece, very fast delivery from Digikey.
I revived a TRC-88 USB manpack with them versus custom crystals in the receiver LO and transmitter HFO, they work just fine, pretty easy to implement. Just add + 5 volts. Take a look here for details on how I did it.
https://www.n6cc.com/trc-88-hf-cwssb-transceiver/Thanks to W9RAN for the heads up on these versatile parts!
Tim
N6CC