4. 1 2
Tone Squelch Operation
When the optional FTS - 8 Tone Squelch Unit is
i n s t a l l ed ( and the FTE - 2 Burst U nit is no t
i n s t a l l e d ) ,
the FT -767 GX can be used for
si l e n t monitoring o f busy c h annels in the FM
mode, as well as for accessing repeaters r e
quiring C TCSS tones o n V H F or UHF ( when the
a ppro p ri a t e Band Mo d u l e s are ins t a l l e d ) .
Two different tones may b e stored, one i n each
o f the V F O s.
A v ai l ab l e to n e freque nci e s a r e
listed i n T a b l e 3 on pag e 36.
To set the CTC SS ( subaudibl e ) tone frequency;
( I ) Press the o r ange FUN C ( T SET ) k e y
t wice. The dis p l ay now shows t h e se l
ected tone frequency (in Hz ).
( 2) Use t h e BAND/M C H keys to se l e c t t h e
d e si r e d to n e f r e q u e n c y f ro m t ho s e
disp l a y ed.
( 3 ) Press H/G (ENT) to store the displayed
to n e a n d r e t u r n to t h e o p e r a ti ng
freq u e n cy.
To activ a t e to ne s q u e l c h monitoring, t u r n t h e
S QL co n t ro l co u n t e rc lockwise i n to t h e c lick
s top (T S Q L po sition ) . The receiver wi l l re
m ain si l e n t u n til a sig n a l is received wi t h a
s ubaudib l e to ne m a t ching t h a t prog r a m m e d in
the VFO.
Other signals not having the correct
tone wi l l c ause the BU SY indic a tor to g low,
b u t wi l l no t op e n t h e sque l ch .
T o t r a n s m i t the progr a m m e d to ne, t h e T EN C
switch must be ON ( depressed ).
The subaudible
tone wi l l be s e n t a t a l l ti m e s whi l e the PTT
s witch is c losed.
4.1 3
Tips for SSB ( LSB/USB) Operation
A l t hough a l l of the co n t ro l s and f e a t u r e s
a v ai l a b l e fo r S S B o p e r a tion h av e a l r e a dy b e e n
d e s c ribed, o b t aining o p ti m u m p e r fo r m an c e o n
S S B modes requires ski l l fu l m anipu l a tio n o f
t h ese f e a t u r e s b y t h e o p e r a to r, b roug h t o n
m ainly by experience and experimentation.
The
ti ps in this sec tion are p rovided to
y o u r experi m e n t a tion , a n d ( ho p e fu l l y )
s ho r t e n l e a r ni ng tim e.
4. 1 3. 1
Weak S ignal S SB Reception
guide
he l p
W e a k S S B sig n a l s, b y de fi ni tio n, a r e very
c lo s e to the ba ckground noise l e v e l , sugge s
ti ng t h at you wi l l w a n t to t ake a l l s t e p s
possible to decrease the effects of background
noise whi l e e n h a ncing t h e desired sign a l ( s ) ,
b y t aking every advan t ag e o f t h e di f f e r ences
between the two.
O f course, squelch cannot be
u s e d, since t h e SSB s q u e l c h ci rcui t ry c a n no t
dis ti nguish b e tween noise a n d sig n a l s.
T h e noise b l anker c a n b e u s e f u l fo r r e ducing
noise, and m ay be l e f t on an d set to a very
low l e v e l, to b l a n k swi t c hing t r ansi e n t s t h a t
o f t e n . occur ( i f you live i n a c rowded a re a ) .
T h e b l anker c a n so m e ti m e s h e l p a li t t l e wi t h
lig h t ni ng c r a shes,
b u t c a n no t s top ' whi t e '
b a n d noise.
I f high leve l p u l s e noise a p p e a r s
( li k e the ' woo dpecker ' ) , j u s t a d v a n c e t h e
b l an ki ng (NB ) con t ro l. A s t h e n a t u r e o f b a n d
noise v aries wi d e l y wi t h ti m e,
f r e q uency,
s e a son and s t a tio n lo c a tio n , you wi l l h ave to
experiment.
The fast A G C setting can be useful for setting
t h e noise b l a nker wi t h so m e t y p e s o f noise i f
t h e l e v e l i s high enough to cause S - m e t e r
d e f l e c tion.
A dvance t h e NB co n t ro l j us t to
the point where the S - m eter deflection no lon
g e r d ro ps.
F ast A G C a l so h e l ps you to h e a r
sig n a l s ' a ro u n d ' noise p u l s e nois e, by c ausing
r e c ei v e r g ai n to r e co v e r q ui ck l y a f t e r a
pulse.
However, fast A G C also m akes listening
a bi t of a s t r ain, so t r y m ediu m or s lo w A G C
o n c e you have a s t a tio n t u n e d in.
O nce the noise blanker and A G C are set up, you
wi l l w a n t to t ake s t e ps to t ailor receiver
s e n sitivity ( sig na l - to - nois e r a tio ) .
T h e ob
j e c tive here is to o b t ai n a b ac kgro u n d noise
l ev e l that is on l y a s lig h t his s ( o r no thing
a t a l l ! ) , wi t hout loo si ng a n y w a n t e d sig n a l s.
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Summary of Contents for FT-767GX
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