Bob Dengler wrote:
A 5 watt signal is +37 dBm. *Typical* transmitter sideband noise with a
good radio set is likely -90 to -100 dB below the carrier at 2.5 mHz
spacing. Many receivers intended for repeater service will hear a signal
at -125 dBm. +37 minus 90 is negative 53 dBm. Now take -125 and subtract
-53, and the duplexer will have to provide 62 to 72 dB of isolation.
That sounds right. Still significantly lower than what's required for 600
kHz spacing.
Now, use a PLL exciter and your right at that -40 number for both.
Kevin Custer
Interesting. I know about PLL exciters for Mastr IIs but never seen one
for an MVP; do they exist?
They do not. One from a Mastr II would have to be scabbed in, and
there may not be enough room.
Kevin
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