Yaesu VX-120 Series, Technical Supplement

Page: 10 / 32

10
Alignment
Test Setup
Set up the test equipment as shown below for transceiver
alignment.
Entering the Alignment Mode
Alignment of the VX-120/-170 is performed using a front
panel software-based procedure. To perform alignment
of the transceiver, it must first be placed in the “Align-
ment Mode,” in which the adjustments will be made and
then stored into memory.
To enter the Alignment mode:
1. Press and hold in the
PTT and MONI switches turning
the radio on. Once the radio is on, release these two
switches.
2. Press the keypad in the following sequence:
VX-120
: [
WX
(
EMG
) ]
[ LOW
(
LOCK
)
SET
]
[
REV
(
HOME
)]
[
(
MHz
)]
[
(
MHz
)]
VX-170
: [ (
MHz
)]
[ 0
(
SET
)]
[ 2
(
CODE
)]
[
2
(
CODE
)]
[ MR
(
SKIP
)]
3. Press the [ F
] key to cause “
A0 REF.xxx
” to appear on
the display for five seconds, this signifies that the trans-
ceiver is now in the “Alignment Mode.”
PLL Reference Frequency
1. Tune the frequency to 145.050 MHz, then set the trans-
mit power level to “LOW.”
2. Press the [ F
] key, then press the [
MR
(
SKIP
)] key to set
the alignment parameter to “
A0 REF.xxx
,” if needed.
3. With in five second of appearing the “
A0 REF.xxx
” on
the display, press the PTT switch to activate the trans-
mitter, adjust the DIAL knob so that the counter fre-
quency reading is 145.050 MHz (±100 Hz).
“TX S
ECTION
” A
LIGNMENT
S
ETUP
7.5 V DC
Regulated Power Supply
SINAD
Meter
RF Signal
Generator
8
Dummy Load
Ω
SP GND
“RX S
ECTION
” A
LIGNMENT
S
ETUP
Inline
Wattmeter
RF Sampling
Coupler
AF Signal
Generator
9.9 V DC
Regulated Power Supply
50
Dummy Load
Ω
Frequency
Counter
Frequency
Counter
MIC GND