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Hi All,
I have been thinking about weak signals on 136
using QRS and DFCW. These techniques enable signals to be read which are
buried 30db down in the noise(see Extreme narrow bandwidth techniques ON7YD )
Does this mean that signals 30db down on atmospheric noise are seen,if so what
about the noise from the RX pre-amp ? In my case this is about 20/30 db less
than the Ant. noise,so would I be looking at the pre-amp noise or is this also
reduced by the narrow bandwidth ?
I should like to improve the noise performance of
my pre-amp.
filter combination. and would appreciate any
information on high performance circuits or amp. units. Is the MAR6 likely to be
worth while.
By the way if my thoughts are correct this may be
why high Q loops are reported to be superior to lower Q types, higher signal
output overriding amp. noise. Any ideas ?
73s Laurie.
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