5. Listen to the background noise from the speaker. Turn the SQUELCH con
tr ol slowly clockwise until the noise JUST disappears (no signal should be
present). Leave the control at this setting. The SQUELCH is now properly
adjusted. The receiver will remain quiet until a signal is actually received. Do
not advance the control too far, or some. of the weaker signais will not be
heard.
6. Set the CHANNEL selector switch to the desired channel.
7. Set the RF gain control fully clockwise for maximum RF gain.
8. Adjust the VOICE LOCK control to clarify the SSB/CW signais or to opti-
mize AM/FM signais.
OPERATING PROCEDURE TO TRANSMIT
1. Select the desired channel of transmission.
2. Set the MIKE GAIN control fully clockwise.
3. If the channel is elear, depress the push-to-talk switch on the microphone and
speak in a normal voice.
RECEIVING SSB SIGNALS
There are four types of signais presently used for communications in the
Citizens Band: FM, AM, USB, and LSB. When the MODE switch on your unit is
placed in the AM position, only standard double-sideband and in FM position,
only frequency déviation, full carrier signais will be detected. An SSB signal
may be recognized while in the AM or FM mode by its characteristic “Donald
Duck” sound and the inability of the AM or FM detector to produce an intel
ligible output. The USB and LSB modes will detect upper sideband and lower
sideband respectively, and standard AM signais.
SSB réception differs from Standard AM réception in that SSB receiver does
not require a carrier or opposite sideband to produce an intelligible signal. A
single-sideband transmitted signal consists only of the upper or the lower side
band and no carrier is transmitted. The élimination of the carrier from the AM
signal helps to eliminate the biggest cause of whistles and tones heard on chan-
nels which make even moderately strong AM signais unreadable. Also, SSB takes
only half of an AM channel, therefore two SSB conversations wilFfit into each
channel, expanding the 120 AM channels to 240 SSB channels. The réduction in
channel space required also helps in the receiver bęcause only half of the noise
and interférence can be received with 100% of the SSB signal.
An SSB signal may be received only when the listening receiver is functioning
in the same mode. In other words, an upper sideband signal (USB) may be made
intelligible only if the receiver is functioning in the USB position.
If a lower sideband (LSB) signal is heard when the receiver is in the USB
mode, no amount of tuning will make the signal intelligible. The reason for this
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