[CQ-Contest] Re:

[Ed]

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Michael Tope wrote:
Pete,
If the output frequency of the trasnmitter is steady, then, yes, the
signal bandwidth is a function of rise and fall time. If on the other
hand, the output frequency of the trasnmitter is still changing while
the output envelope is rising, then the envelope shape may not tell
the whole story. If for example, as Tom suggests, the transmitter and
receiver share a frequency synthesizer and there is a frequency offset
between receive and transmit frequencies that requires the synthesizer
to be reprogrammed or shifted when switching between transmit and
receive, then it possible for the transmitter frequency to be still in
the process of settling-in when the transmitter is turned on
(synthesizers tend to oscillate about their target frequency for a few
cycles of their natural frequency after they change frequency) .

Mike, W4EF.......
---------------------

With all due respect to the wisdom of these posts, it's beginning to
sound like the &*)(% radio uses knife switches to go from receive to
transmit.

There's not a person alive who could physically react in such a time
frame.

73
Ed


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