BASIC Radio Question
Thanks
"Milos Forman" wrote in message
nk.net...
I was getting confused too.
"Jonathan Ganz" wrote in message
...
Gilligan,
Could you possibly switch to another personality... it's just too
confusing to read two totally different viewpoints from bob... one
rational, the other foolish and stupid.
"Bobsprit" wrote in message
ink.net...
VHF radio is FM which is the modulation of a sine wave carrier so that
the
instantaneous frequency differs from the carrier frequency by an
amount
proportionate to the instantaneous amplitude of the modulating wave.
Single sidebandband suppressed carrier modulation is a form of
amplitude
modulation whereas the carrier frequency and one sideband of the
modulated
carrier is suppressed.
For S/N the NBFM (VHF) performance is the same as DSB-AM in the
presence
of
white noise. The SSB performance is superior to both and to SSB-AM
because
all the signal power is is placed into a narrower spectral band than
the
former.
SSB detection requires the use of synchronous demodulation, preferably
with
phase synchronization, otherwise a Donald Duck type voice appears.
Since you never venture far offshore, dixie cups with strings will
provide
more than adequate performance.
RB
"Bobsprit" wrote in message
...
I'm not clear on marine SSB radios. Can someone explain how they
differ
from
standard VHF? A friend is now offering me a pretty expensive Icom
SSB.
I
doubt
I have a need for it, but it's basically free. I may just tell him
to
sell
it
on ebay. I was thinking of adding a AM/SSB (CB) radio to the boat
which
would
be better than the GMRS.
So can someone explain what the marine SSB is? Is it VHF with upper
and
lowers?
Thanks in advance...
RB
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