Initial Check; Frequency Selection; Receive Operation - Yaesu FT-902DM Instruction Manual

OPERATION
The tuning procedure for this transceiver is not
complicated. However, care should be exercised
when tuning so that peak performance of the
equipment is secured. The following paragraphs
describe the procedure for receiver and transmitter
operation.
INITIAL CHECK
Before connecting the transceiver to a power
source, carefully examine the unit for any visible
damage. Check that all modules are firmly in
place and that the controls and switches are op-
erating normally. Make sure that the voltage spe-
cification marked on the rear panel matches your
supply voltage, and that the line fuse on the rear
panel matches the supply voltage; for 117 VAC,
use a 5 amp fuse, and for 220 VAC use a 3 amp
fuse. For DC operation a fuse holder is installed
in the DC cable, and a 20 amp fuse should be
installed here.
FREQUENCY SELECTION
Frequency readout for the FT-902DM includes
both analog and digital readout. The analog read-
out dial shows calibrations at the 100 kHz and
10 kHz points, and is marked, as well, in 1 kHz
increments for fine tuning. The digital readout
displays all digits of the operating frequency, with
resolution down to 100 Hz accuracy.
RECEIVE OPERATION
(1) Preset the controls and switches as indicated:
POWER...... OFF
HEATER..... OFF
V FON ceo. Switch depressed
VOX GAIN... .PTT position
RF GAIN ... .Fully clockwise
AF GAIN ....Adjust subsequently for com-
fortable level
BAND....... Desired band
MODE....... Desired mode
PRESELECT. .Desired band segment
(4) When pulse-type noise is encountered, the
NB (Noise Blanker) switch should be acti-
vated, providing effective suppression of
this type of noise.
(5) Rejection of adjacent-channel interference
may be accomplished by several means. The
REJECT control may be utilized to place a
steep-skirt 30 dB notch attenuation on any
interfering signal within the IF passband.
The WIDTH control varies the center fre-
quency of one of two IF filters (the other
is fixed and presents a boundary for narrow-
ing the passband). Varying the WIDTH con-
trol varies the IF selectivity from approxi-
mately 300 Hz to 2.4 kHz (at 2.4 kHz the
WIDTH control is at "0" and the two filters
have the same center frequency). Clockwise
rotation from the center ('0') position
makes the passband narrow toward the high
frequency side, while counter-clockwise ro-
tation narrows the passband on' the low-
frequency side.
(6) For CW reception, the APF (Audio Peak
Filter) may be activated. This filter has a
100 Hz peak bandwidth with very steep
skirts so as to provide single-signal reception
for CW, with insertion loss of less than ] dB
when the APF control is tuned exactly to
the signal frequency. The APF FREQ control
varies the peak frequency from approximately
400 Hz to 900 Hz. The operator will observe
that the APF system provides a significant