FW.
56-
T'r'Gpnoidol
wa~form
Mowing
n~flJlj~
modulation clipI'm,.
SSB APPLICATIONS
The
balan~
modulator of
In
SSB tranllrnilter .hould
eliminate
mOllt
of
the
carrier freque""Y IUowinS only
one of
the
~idebands
to
be
hroadcast. The
lM:0l'e
adlpter
omput
will
~how
the pretlellU of a
c.rrier
in one of two
ways.
FiS. 5lI
.how.
what
happena when
the
balanced
modulator
i.
milllldjueted lli&htly
to
allow
IIOme
of
the
carrier
to JIIlIII through.
The
.....veform beroTIlell modu·
lated.
Fig.
58-Poorly
tldj~tN
bil/anc<M
modulator in·
~ae.
AM
modulation from SSB
tran.
mitter.
In
adjust;n,
the luolanced modulator, simply set the
bal·
snced modulator for
the
leut
amount
of
modulation on
the
sinlle
lone output ,igna1.
ssa
otE·TONE
METHOD
ssa
TWO·
TONE
METHOD
Fig.
60-Pooriy
tldjuat·
ed
lxI/an«d modulator
durort.
cro,,·o~'tr.
Fig.
59-f'ro~riy
ad·
j~ted
balan«d modu·
lalor
product.
c~n.
~~r.
Using two
b&la~d
<<In
.... the w.veform in
Fig.
fi9
should result. If there
is
artY
carrier information in
the
RF output, the waveform will not close
al
the
baaeline.
but have the cerrier present
at
th_
poin!JI.
To adjustthe
balanced modulator using
the
two·tone input provided
by
theCB42.
~imply
adju.t
the balanced modulator untH
the nulls of
the
..
ave/onn just
c1tlo!le_
Fig. 51-Minimum
AM
modulation
fewlt.
from
pro-
~r
aettilll
of
ba/anc<ed
modulator
In SSB
tronamitter.
tr
a
linsle
tone ill uaed to modulate
the
SSB lranllmitler.
lh~
n!8ult
~hould
be
a aingle frequency output. This out-
put
shO\lld be offsel from the carrier frequency
by
the fre·
quency of the modulating aigna!. Fig.
5'1
show.'
pro-
perly adjuated bIll.nced modulator output. Note
that
the
ainlle
tone input produces a
sinlle
unmodulated carrier.
46
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