Vince asked:

Which of these candidates would support adding a Mode A linear transponder to FOX, or any type of linear transponder for that matter. FOX will already have a 2m receiver all you'd need to add is a 10m downlink transmitter. Use a tape measure tape for the antennas.

Not very practical ides -- sorry.

FOX is a 1U Cubesat, 10cm=4" on a side. Kinda hard to fit 10M dipole (which would be ~16 ft long, fed in the middle). You can't do it with a monopole because the 4" box doesn't have enough size to feed a monopole against. And with a 4" cube (even with deployable panels) we can only expect a total of a few watts (orbit average) of power.

The laws of physics and engineering are rather unforgiving!

73, Tom