Any kind of busy detection circuit will need to provide detection for the entire band of frequencies you are going to be transmitting in. In fact, this was one of my recommendations to the ARRL.
It should not be as much of a problem as you have with Pactor since the mode will likely have one set bandwidth and it will adjust for the conditions with the way the protocol works within that BW. Pactor, in order to be backward compatible, needs to operate in a ~ 500 Hz space for initial interrogation of the stations and then it may expand to P3, if it is found that it is possible to do so with P3 modems on both ends. If they are P1 or P2, then they would stay at around 500 Hz. 73, Rick, KV9U jgorman01 wrote: > I suspect an activity detector IS going to have a problem knowing if > there is another close by signal while the auto station is > tranmsitting. In fact, so will a client, while it is transmitting. > If, while transmitting, the busy detector would prevent expanding the > bandwidth if there is a close by signal, then I see no reason this why > this wouldn't prevent qrm'ing of other nearby qso's. >
