Robin2:
The other thing that confuses me about the high servo update frequency is the business of multiplexing the signals for several channels for transmission between the transmitter and the receiver. If there is a 50Hz update frequency there is about 20 msecs between pulses, Since the longest pulse is a little over 2msecs there is "space" for about 8 channels within the 20 msecs.If you increase the update frequency it seems to me the "space" for multiple channels is correspondingly reduced. And I can't see any value in the receiver getting pulses at 50Hz and repeating some of them at a higher frequency on individual channels - there would be no additional data.
But I may be completely dazed and confused.
...R
Your not confused, that old standard R/C PPM data stream only allowed for updating individual channels at around a 50 Hz rate. I suspect the newer R/C spread spectrum radios use a different PPM frame rate and therefore might support a newer higher frequency servos?