FT-920 Operating Manual
21
(7) METER SELECT Switch
This switch is used to select the display function of
the transmission multimeter, with the selections be-
ing provided in the following sequence:
ALC: ALC Voltage.
SWR: SWR as observed by the transmitter PA.
COMP: Speech Processor Compression level.
VOLT: Final amplifier transistor supply voltag
(also displayed on receive).
AMP: Final amplifier transistor drain current.
ALC: ALC Voltage
(return to beginning of loop).
(8) IPO Switch
The Intercept Point Optimization button switches the
receiver RF preamplifier on and off. When the switch
is pressed, the “IPO” icon appears on the display
panel, and the receiver RF preamplifier is bypassed.
When this switch is pressed again, “IPO” will disap-
pear, and the RF preamplifier returns to operation.
Best receiver sensitivity occurs when “IPO” is off.
However, the RF preamplifier may not be necessary
in noisy locations or on the lower frequencies, in which
case the IPO feature will provide improved immunity
from intermodulation.
(9) A
TT Switch
This switch may be used to reduce the input receive
signal in one S-Unit steps, starting at 0 dB (no at-
tenuation), and sequencing through [6 dB] Þ [12 dB]
Þ [18 dB] Þ [0 dB]. . .
The attenuation level is shown on the display panel.
Best sensitivity will, of course, occur when no attenu-
ation is used.
(10) AGC Switch
This switch selects the recovery time for the receiver
AGC (Automatic Gain Control) system. The selec-
tions available are, in order:
AGC FAST: Fast receiver recovery time.
AGC SLOW: Slow receiver recovery time.
AGC OFF: AGC system disabled.
AGC FAST: Fast receiver recovery time
(return to beginning of loop).
The current receiver recovery time constant is shown
on the display panel.
? If “AGC OFF” is selected, the S-meter (which moni-
tors AGC voltage) will cease to function.
(11) M
IC GAIN Control
This control adjusts the microphone input level in the
SSB and AM modes. Clockwise rotation increases
the microphone gain level.
(12) RF P
WR Control
This control adjusts the transmitter’s power output,
with a range of 10 ~ 100 Watts, and adjustment is
available in all modes. Clockwise rotation increases
the power output.
(13) AF GAIN Control
This control adjusts the receiver volume level pre-
sented to the speaker or headphones. Clockwise ro-
tation increases the volume level.
? Note that this control does not affect the audio
level presented to the rear-panel AF O
UT and DATA
jacks.
(14) RF G
AIN Control
This control adjusts the gain of the receiver’s RF and
IF stages. Clockwise rotation increases the RF Gain
level for best sensitivity, and the normal operating
position for this control is fully clockwise.
? Counter-clockwise rotation of the RF GAIN con-
trol, besides lowering the receiver gain level, will
cause the S-meter to deflect upward, as though a
strong signal were present.
(15) NARROW Switch
This switch is used to activate optional narrow filters,
for improved interference rejection. Press this switch
to select the narrow filter; the “NAR” indicator will ap-
pear on the display panel.
(16) MODE Switches
Pressing one of these switches selects the operating
mode. Per the chart below, repeated presses of a
particular switch may cause the precise mode to be
selected from within a mode group (for example,
pressing [SSB] repeatedly toggles between [USB]
and [LSB].
Mode
Switch
Available Mode Selections
SSB
LSB
Ö
USB
CW
CW (LSB)
Ö
CW (USB)
AM
AM
FM
FM
DATA
DATA LSB
Õ
DATA USB
Õ
DATA FM
Õ
DATA LSB
Õ
(RTTY/FSK) (PKT/AFSK) (PKT/AFSK) (RTTY/FSK)
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