wrote:

"How wide is the deviation? "

If you mean the base carrier frequencies they range from about 174
to 210 MHz on these models. I do not now the modulation but I know
each frequency ends in a 0.05. Every one of them, like 210.95,
174,15, they all end in a 0.05. That leads me to believe they run maybe
50KHz deviation ? Europe uses it for FM radio. The US runs 75 KHz.

** Europe also uses 75kHz deviation, its the pre-emphasis that differs.

50uS in Europe and most other places, 75uS in the US, Canada and Japan.


Of course there are sidebands but what are the odds ? And the ones I
have seen, the two channels are displaced by about 10 MHz or more.

** The channel spacing coincides with US, VHF TV stations.

In a given location, prior to digital broadcasting, every second channel was blank. So you had chs 7,9,11 & 13 on the air OR chs 8,10 & 12. This allowed the class licensed use of several radio mics in each of the black bands.

The deviation on such models was usually 30kHz with 75uS pre-emphasis and some form of audio companding.

The best models from Shure, Nady or Vega had exceptional audio quality.



..... Phil