This silliness about evaluating a receiver with an unterminated
(infinite impedance) input has gone far enough.
Why do I care about garbage that may be picked up with an unterminated
front end on a transceceiver that is designed for a 50 ohm antenna
termination.
If you hook a 50 or 100 ohm ( to allow for imperfect match) dummy load
to the antenna terminal and hear birdies then they are possibly of concern.
But it is nonsense to expect no birdies to be picked up in the
unterminated condition. If they are not there this could be good but
could also indicate a low gain system.
If they are not there when terminated with 50 ohms then I know that the
birdie issue is under control for proper use of the transceiver.
Aloha,
John KH7T
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