At 04:56 PM 2/25/01 -0800, 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) .
Would it be feasible to use the same test setup that ARRL uses for
composite noise, but key the transceiver at a standard rate, both with and
without a standard transmit/receive offset, and look for spikes?
73, Pete N4ZR
Contesting is!
The World Contest Station Database
is waiting for your input at
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