Ssb Operation - Icom IC260-A Instruction Manual

SSB OPERATION
1.
RECEIVING
After connecting an antenna, microphone, etc., set knobs and switches as follows.
MODE SELECT SWITCH USB or LSB
RIT CONTROL "OFF" position or center (12 o'clock) position
NOISE BLANKER SWITCH |
OFF (OUT)
VFO GANG SWITCH "SEP" (Pushed IN)
AGC SWITCH normal (OUT) |
VOLUME CONTROL and POWER SWITCH
Completely counterclockwise (OFF position)
SQUELCH CONTROL and RF POWER SWITCH :
Completely counterclockwise (Pull switch is normal position.)
VFO/MEMORY SWITCH "А"
The other knobs are unrelated to receiving and need not be set at this time.
In SSB operation there is both a USB (upper side band) and an LSB (lower side band).
USB is usually used on the band, while LSB is usually used on the downlink of the satellite
communications. Select the mode according to your use.
Now turn ON the power switch. The meter lamp will be illuminated and "145.000.0"
(^145.600.0" when VFO/MEMORY Switch is іп "B" position.) will be shown on the LED
readout. Slowly turn the VOLUME Control clockwise to a comfortable level. Rotate the
tuning knob until a signal is received. The meter needle will move according to the signal
strength, so tune for the highest possible meter reading and the clearest audio. If you cannot
get a clear signal, you may be receiving in the opposite sideband. If so, change the MODE
SELECT Switch to the proper sideband.
The VFO's іп the IC-260A/E change іп 100Hz steps. Therefore the maximum possible dif-
ference in your receiving frequency and the received signal frequency is 50Hz. However, for
normal voice signal reception, a difference of 50Hz is negligible and indeed may be hard to
distinguish. Since the frequency is changed in 100Hz steps with the ІС-260А/Е, as opposed to
continuous variable frequency systems, tuning is simplified and more accurate.
If squelch operation is required to cut out noise when no signal is received, turn the SOUELCH
Control clockwise until the noise from the speaker stops and leave it just below this threshold.
For tuning and Memory Channel operation refer to "HOW TO TUNE" on page 13 and
"MEMORY CHANNEL OPERATION" on page 18.
NB (NOISE BLANKER)
Set the noise blanker ON (pushed IN) when there is pulse type noise, such as ignition noise
from automobile motors. Noise will be suppressed and even weak signals will be received
comfortably. The noise blanker may not work as effectively when there is a strong signal on a
nearby frequency or when there is continuous (not pulse type) noise.
AGC (AUTOMATIC GAIN CONTROL)
The ІС-260А/Е has a fast attack/slow release AGC system which holds the peak voltage of
—20—