Tone Squelch Operation; Tips For Ssb (Lsb/Usb) Operation; Weak Signal Ssb Reception - Yaesu FT-767GX Operating Manual

4.12 Tone Squelch Operation
When the optional FTS-8 Tone Squelch Unit is
installed (and the FTE-2 Burst Unit is not
installed), the FT-767GX can be used for
silent monitoring of busy channels in the FM
mode, as well as for accessing repeaters re-
quiring CTCSS tones on VHF or UHF (when the
appropriate Band Modules are installed).
Two different tones may be stored, one in each
of the VFOs. Available tone frequencies are
listed in Table 3 on page 36.
To set the CTCSS (subaudible) tone frequency;
(1) Press the orange FUNC (T SET) key
twice. The display now shows the sel-
ected tone frequency (in Hz).
(2) Use the BAND/MCH keys to select the
desired tone frequency from those
displayed.
(3) Press H/G (ENT) to store the displayed
tone and return to the operating
frequency.
To activate tone squelch monitoring, turn the
SQL control counterclockwise into the click
stop (T SQL position). The receiver will re-
main silent until a signal is received with a
subaudible tone matching that programmed in
the VFO. Other signals not having the correct
tone will cause the BUSY indicator to glow,
but will not open the squelch.
To transmit the programmed tone, the T ENC
switch must be ON (depressed). The subaudible
tone will be sent at all times while the PTT
switch is closed.
4.13 Tips for SSB (LSB/USB) Operation
Although all of the controls and features
available for SSB operation have already been
described, obtaining optimum performance on
SSB modes requires skillful manipulation of
these features by the operator, brought on
mainly by experience and experimentation. The
tips in this section are provided to guide
your experimentation, and (hopefully) help
shorten learning time.
4.13.1 Weak Signal SSB Reception
Weak SSB signals, by definition, are very
close to the background noise level, sugges-
ting that you will want to take all steps
possible to decrease the effects of background
noise while enhancing the desired signal(s),
by taking every advantage of the differences
between the two. Of course, squelch cannot be
used, since the SSB squelch circuitry cannot
distinguish between noise and signals.
The noise blanker can be useful for reducing
noise, and may be left on and set to a very
low level, to blank switching transients that
often occur (if you live in a crowded area).
The blanker can sometimes help a little with
lightning crashes, but cannot stop 'white!
band noise, If high level pulse noise appears
(like the 'woodpecker'), just advance the
blanking (NB) control. As the nature of band
noise varies widely with time, frequency,
season and station location, you will have to
experiment.
The fast AGC setting can be useful for setting
the noise blanker with some types of noise if
the level is high enough to cause S-meter
deflection. Advance the NB control just to
the point where the S-meter deflection no lon-
ger drops. Fast AGC also helps you to hear
signals 'around' noise pulse noise, by causing
receiver gain to recover quickly after a
pulse. However, fast AGC also makes listening
a bit of a strain, so try medium or slow AGC
once you have a station tuned in.
Once the noise blanker and AGC are set up, you
will want to take steps to tailor receiver
sensitivity (signal-to-noise ratio). The ob-
jective here is to obtain a background noise
level that is only a slight hiss (or nothing
at all!), without loosing any wanted signals.
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