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Common gate jfet used as bidirectional amplifier?

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neazoi

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Since the drain and source of a jfet, can be interchanged, can a jfet in common gate configuration be used as a bidirectional amplifier (HF frequencies)?

The source impedange will be low and the drain impedance will be high, but the antenna could be connected to the source and the RX/TX to the drain (high impedance RX/TX)
 

Proceed to actual circuit analysis to see why it probably doesn't work.

Although the terminals are interchangeable, the actual device function depends on applied voltage levels and respective current flow. You can of course apply a signal to the output of any amplifier and get a certain signal at the input according to s12 (reverse gain). But is this what you expect to drive a TX antenna? Better use a TR switch.
 

Proceed to actual circuit analysis to see why it probably doesn't work.

Although the terminals are interchangeable, the actual device function depends on applied voltage levels and respective current flow. You can of course apply a signal to the output of any amplifier and get a certain signal at the input according to s12 (reverse gain). But is this what you expect to drive a TX antenna? Better use a TR switch.

No, the whole point I was thinking about it, was to avoid switching. So it can't be done like you say.
Thanks!
 

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