Vertex Standard FT-1807M - Manual (Page 10)

10
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 tempera-
ture be the same as that of the transceiver and test
equipment, and that this temperature be held con-
stant between 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 possible, alignments
should be made with oscillator shields and circuit
boards firmly affixed in place. Also, the test equip-
ment must be thoroughly warmed up before begin-
ning.
Note: 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.
Entering the Alignment Mode
Alignment of the FT-1807M 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
ˆ Rotate the DIAL knob to set the alignment param-
eter to “435.000 rF 435.000 rF 435.000 rF 435.000 rF 435.000 rF.”
ˆ Press the [D/MR(MW)] key to enable adjustment
of the “PLL Reference Frequency.”
ˆ Press the PTT switch to activate the transmitter,
adjust the DIAL knob so that the counter frequency
reading is 435.100 MHz (±200 Hz).
ˆ Press the [D/MR(MW)] key.
RF Front-end Tuning
ˆ Inject a 435.100 MHz signal at a level of –10 dBµ
(with 1 kHz modulation @±3.5 kHz deviation)
from the RF signal generator.
ˆ Rotate the DIAL knob to set the alignment param-
eter to “435.100 tn 435.100 tn 435.100 tn 435.100 tn 435.100 tn.”
ˆ Press the [D/MR(MW)] key to enable adjustment
of the “RF Front-end Tuning.”
ˆ Adjust the DIAL knob so that the maximum
SINAD.
ˆ Press the [D/MR(MW)] key.
Alignment
T
EST
E
QUIPMENT
S
ETUP
MIC SW2
MIC SW1
GND +8V
MIC INPUT
PTT/CLONE
FT-1807M
Inline
Wattmeter
SINAD Meter Deviation Meter
Frequency
Counter
RF
Signal Generator
AF
Signal Generator
RF
Signal Generator
50-Ohm
Dummy Load
MIC
ANT
EXT SP
RF Sampling
Coupler
DC INPUT