1. Yes the shift selectability of the tx makes it compatable with all four major brands FM Rx's.

2. Yes the radio is still shift selectable without using the Spectra module and yes you can go to the field with seven different models on all different frequencys, both modulation shifts and switch back and forth in one minute with the Spectra.

If you purchase your Eclipse without the Spectra module you will eventually regret it I did both for the loss of function and the additional expense of buying one later. The Spectra system is unparalleled in the industry untill you are spending 1400 dollars or more that is seldom appreciated untill you really start to use it.

Just a very satisfied user,
John