Icom IC-R71A Instruction Manual page 8

7. FUNCTION KEY
Increases the function of the AM MODE SELECT and
the MEMORY WRITE switches by pushing this key switch
first.
8. PREAMP/ATT (Attenuator) SWITCH
Switches RF preamplifier and attenuator in the RF circuit.
When the switch is in the OFF position, both preamplifier
and attenuator are removed from the circuit, and incoming
signals will be fed to the receiver directly.
When using a small antenna or receiving a weak signal, set
the switch in the "PRE" position, and the preamplifier is
put in the RF circuit and provides higher sensitivity.
When nearby signals interfere with reception, or receiving a
very strong signal, set this switch in the "ATT" position.
This removes the preamplifier from the circuit and inserts
the attenuator into the circuit. This gives about 20dB
attenuation.
For normal operation leave this switch in the "OFF" position.
9. FILTER SWITCH
Selects one of the second IF (9MHz) filters to improve the
selectivity.
10. PHONES JACK
Accepts a standard 1/4 inch headphone plug for headphones
of 4 ~ 16 ohms. Stereo phones can be used without modi-
fication.
11. RECORDER JACK
Accepts a 3.5mm mini plug for a tape recorder to record
receiving signals. The output is a certain level regardless of
the position of the AF GAIN control.
12. AF GAIN CONTROL
Controls the audio output level. Clockwise rotation
increases the level.
13. RF GAIN CONTROL
Controls the gain of the RF section. Clockwise rotation
gives the maximum gain. As the control is rotated counter-
clockwise, the needle of the METER rises, and only signals
stronger than the level indicated by the needle will be
heard.
14. SQUELCH CONTROL
Sets the squelch threshold level. To turn OFF the squelch
function, rotate this control completely counterclockwise.
To set the threshold level higher, rotate the control clock-
wise.
15. TONE CONTROL
Controls the receiver audio tone. Adjust the control to
provide comfortable reception.
16. DIMMER SWITCH
By pushing this switch in, the intensity of the meter illumi-
nation and frequency display is reduced. Use this in the
dark to prevent glare.
17. SCAN START/STOP BUTTON
Starts and stops any of the scan functions. When depress-
ing it again to restart the scan, it will start from the stopped
frequency in the programmed scan, or from the highest
memory channel in memory scan.
18. MODE SELECTIVE SCAN SWITCH
When this switch is pushed, only memory channels stored
with the operating mode which is displayed on the fre-
quency display just prior to pushing this switch, are selected
by turning the tuning control or scanning.
19. REMOTE CONTROL SWITCH
Switches the optical remote controller circuit (option).
When this switch is pushéd in and locked, the remote
controller circuit will be turmed on and the REMOTE CON-
TROL ENABLE INDICATOR will be lit.
20. TUNING CONTROL
Rotating this control clockwise increases the frequency or
the memory channel number, while rotating it counter-
clockwise decreases it. The frequency changes by 10Hz in
any mode. In 10Hz step tuning rate, by turning the tuning
control faster, the 50Hz step tuning rate is automatically
selected. This makes it very convenient to change fre-
quency quickly over a wide range.
This control is also used to select the operating band while
the BAND SELECT FUNCTION switch is depressed.
21. TUNING RATE SWITCH
By pushing in this switch, the operating frequency is
changed to correspond to 1KHz increments in any mode.
At the same time, the 100Hz digit on the display is cleared
to show '0'. When this switch is pushed again and released,
the frequency is changed normally. This switch allows you
to quickly change over a great frequency range.
22. BAND SELECT FUNCTION SWITCH
By pushing in this switch, the operating band is changed
by turning the TUNING CONTROL.
The operating frequency is changed in 1MHz steps but the
lower digits do not change.
23. VFO/MEMORY SWITCH
Switches between VFO operation and MEMORY CHAN-
NEL operation.
24. DIAL LOCK SWITCH
After the IC-R71 is set to a certain frequency by pushing
the DIAL LOCK switch, the VFO is electronically locked at