JTM said:
I want to use a Radiotronix 433 MHz transmitter and reciever together (so I
can TX and RX from the same device) and want to know if there is a way I can
use the same antenna for both.
It depends on the bandwidth ofthe antenna and whether or not you want to
operate in simplexx or duplex mode.
Simplex is simple, all you do is use a relay or diodes to switch between
transmitter and receiver and you can use the same frequency for both
transmit and receive. You cannot, of course, receive while you are
transmitting.
Duplex, that is, the ability to transmit and receive simultaneously, on the
other hand, requires different frequencies for transmit and receive and
usually an isolator circuit between the tx and rx parts of your radio. An
accurate, high power, notch pass filter, tuned to the receive frequency is
also useful. The frequencies should be far enough apart that the transmit
signal can be filtered successfully from the receive signal, hence the
bandwidth of the antenna becomes critical.
If you need to use duplex operation then you need to do a bit of studying,
designing and building. Simplex operation is well named!
Regards
Cap