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Alignment
Alignment Preparation & Precautions
A 50-Ohm RF load and in-line wattmeter must be
connected to the antenna jack in all procedures that
call for transmission; alignment is not possible with
an antenna. After completing one step, read the next
step to see if the same test equipment is required. If
not, remove the test equipment (except dummy load
and wattmeter, if connected) before proceeding.
Correct alignment requires that the ambient tem-
perature be the same as that of the transceiver and
test equipment, and that this temperature be held
constant between 68 °F ~ 86 °F (20 °C ~ 30 °C). When
the transceiver is brought into the shop from hot or
cold air, it should be allowed some time to come to
room temperature before alignment. Whenever pos-
sible, alignments should be made with oscillator
shields and circuit boards firmly affixed in place.
Also, the test equipment must be thoroughly
warmed up before beginning.
: Signal levels in dB referred to in the alignment
procedure are based on 0dBµ = 0.5µV.
Test Setup
Set up the test equipment as shown below for trans-
ceiver alignment.
50-Ohm
Dummy Load
Signal Generator
RF Sampling
Coupler
Inline
Wattmeter
Deviation Meter
Frequency
Counter
T
Entering the Alignment Mode
Alignment of the FT-1802M is performed using a
front panel software-based procedure. To perform
alignment of the transceiver, it must first be placed
in the "Alignment Mode," in which the adjustments
will be made and then stored into memory.
To enter the Alignment mode, press and hold in the
[ REV ( DW )] and [ D/MR ( MW )] keys while turning the
radio on. Once the radio is on, release these two key.
The transceiver is now in the "Alignment Mode."
PLL Reference Frequency
Rotate the DIAL knob to set the alignment param-
eter to "148.000 rF."
Press the [ D/MR ( MW )] key to enable adjustment
of the "PLL Reference Frequency."
Press the PTT switch to activate the transmitter,
adjust the DIAL knob so that the counter fre-
quency reading is 148.000 MHz (±100 Hz).
Press the [ D/MR ( MW )] key.
RF Front-end Tuning
Inject a 145.100 MHz signal at a level of –10 dBµ
(with 1 kHz modulation @±3.5 kHz deviation)
from the RF signal generator.
Rotate the DIAL knob to set the alignment param-
eter to "145.100 tn."
Press the [ D/MR ( MW )] key to enable adjustment
of the "RF Front-end Tuning."
Adjust the DIAL knob so that the maximum
SINAD.
Press the [ D/MR ( MW )] key.
RF
ANT
DC INPUT
FT-1802M
EXT SP
MIC
AF
Signal Generator
E
S
RF
Signal Generator
SINAD Meter
GND
+8V
MIC INPUT
MIC SW1
PTT/CLONE
MIC SW2
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