Yaesu FT-23R Technical Supplement page 40

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PLL & Transmitter
Set up the te st equipment as shown below for trans­
mitter alignment Adjust the supply voltage to 12.0V
for all steps except Transmitter Output Power.
PLL
VC V (Varactor Control Voltage)
( 1 ) Connect the DC voltmeter between C4 1 7 on the
PLL Unit and chassis ground.
(2) Set the transceiver to 1 44.00 MHz. Key the trans­
mitter and adjust transformer T50 1 on the VCO
B uffer Unit for 1 1 .5 ± 0.05 V DC on the voltmeter.
(3) While receiving on 1 44.00 MHz, adjust trimmer
TC50 1 on the VCO Unit for 0.8 ± 0.05 V DC.
(4) Tune the transceiver to the high band edge and
confirm the correct high-end VCV for the trans­
ceiver version being aligned, in both transmit and
receive, as follows:
Version
Hig h Band Edge
A, C & E
1 48.000 MHz
B & D
1 46.000 MHz
PLL & Transmitter Alignment Setup
50 - ohm
In l ine
Dummy Load
Wattmeter
Freq. Counter
S pectrum
Dev iat i on
Ara l izer.
Meter
A F
Osc i l l oscope
M i l l ivo l tmeter
T s o 1
TC s o 1
V R 2 o o s
V R 2 0 0 4
TC 4 0 1
Tx VCV
Rx VCV
< 1 .6 v
< 1 .3 v
<1 .5 v
< 1 .2 v
ANf
n
n ri MIC
=
AF Generator
=
=
M i l l ivol tmeter
Regulated
1 2 V P S U
PLL & Transmitter A lignment Points
Transmitter Output Po wer
( 1 ) Tune the transceiver to band center ( 145 or 146
MHz), and select high power output (LOW switch
not depres sed).
(2) Increase the supply voltage to 1 2.5 V , and then
adjust VR2005 on the Mother B oard for peak out­
put power on the wattmeter (at least 5 watts with
less than 1 . 5 A supply current).
(3) Now press the LOW button, and adjust VR2005
(again) , this time for 0.5 ± 0. 1 watt.
PL L Reference Frequency
With the transceiver tuned to band center ( 145 or
146 MHz), adj ust TC40 1 on the PLL Unit, if neces sary,
so the display frequency matches the frequency counter
when transmitting.
Modulation L e vel
( 1 ) With the transceiver tuned to band center ( 145 or
1 46 MHz), adjust the AF generator f o r 25-mV
output at 1 kHz to the MIC j ack.
(2) Adjust VR2004 on the Mother B oard f o r ± 4.8 -kHz
deviation on the deviation meter.
AF

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