...

We did that on the uplink receivers for PCSAT-1 and -2 ... to make the receiver about 30 KHz wide.

Yes, this is a similar venture. We did buy a Hamtronics RX ... but decided we could reduce the size significantly.

Yes, its size is very wasteful. But we were surprised that we could hack-saw off one edge of the board and make it fit inside a 4" cubesat and only have to move the first coil a little bit. Though we have since found a smaller receiver, though not crystal controlled...

Even with the hamtronics and modern APRS pic processors, we could easily fit a full 5 Watt APRS digipeater into HALF of a cubesat, leaving the other half for other experiments.