Jack Smith wrote in message . ..

Why don't you define your requirements a bit for us, such as:
(1) power to be switched
(2) speed for switch to operate/release
(3) power available to operate the switch
(4) cost target
(5) frequency range (assumed to be 3-30 MHz since you are working on a
noise canceller)
(6) Isolation between TX and RX port
(7) Maximum acceptable loss

What are these parameters for the T/R switches in the MFJ-1025/1026
noise canceller and the T/R switches in the receiver circuits of
transceivers? The advertising for the MFJ noise canceller explicitly
says that it uses an RF sense T/R switch. I'm sure that transceivers
need T/R switches to prevent the RF from entering the receiver. That
can't possibly be good, because receivers are designed to be very
sensitive, NOT handle large amounts of power.

Jason Hsu, AG4DG