VHF TX/RX switch w/ pin diodes
I am trying to design a solid state TX/RX switch for VHF (2-meter).
DC (when TX)
|
| pin diode
TX-------|---------- Antenna
|
delay line
|
|-------- RX
V (pin diode)
GND
(I am not good at ASCII drwaings !)
My problem is the design of the 1/4 wave line that allows the RX input to be
grounded while showing an open circuit at the antenna. One possible
implementation would be a length of coax but at VHF frequencies that will be
messy. Commercial equipments just use an LC circuit. I am looking for a
pointer to the design of this cicuit.
Thanks,
Bernard
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