Yaesu FT-51R Technical Supplement page 17

PLL Reference Frequency
D With the wattmeter, dummy load and frequency
counter connected to the antenna jack, and while
tuned to the center of the UHF band, key the trans­
mitter and adjust
TC3001
if necessary, so the counter frequency is within 100
Hz of the displayed frequency on the FT-51R.
Transmitter Power Adjustment
umm
D Connect the 50-Q d
meter to the antenna jack. Tune to the UHF band
center and select high power output. Key the
transmitter and adjust
Unit for 5 W ± 0.2W on the meter.
D Tune to VHF band center and select high power
output. Key the transmitter and adjust
the 144-Mother Unit for 5 W ± 0.2W on the meter.
144-Mother Unit Interstage Transformer Alignment
D Connect the RF signal generator to the antenna
jack, and connect the 8-Q dummy load and SINAD
meter to the jack.
EAR
D Tune the transceiver and the
the band center, and inject a signal modulated with
±3.5 kHz deviation of a 1-kHz tone.
D Adjust and
L2015, L2016
Unit for optimum 12 dB SIN AD (at least -9 dBµ for
12 dB SINAD).
CNTL Unit
FT-51R Technical Suoolement
on the 430-Mother Unit,
y load and inline watt­
on the 430-Mother
VR3001
VR2001
RF signal generator to
on the 144-Mother
L2018
430-Mother Unit Interstage Transformer Alignment
Important! Before proceeding, ensure the 430-
Mother Unit is grounded to the transceiver rear case
by reinstalling the five previously removed screws.
0 Unplug the CONTACT Unit from the 144-
Mother Unit assembly. Next, remove the 5 screws
from the shield case on the 144-Mother Unit, and
remove the shield case.
D Remove the 144-Mother Unit to expose the 430-
Mother Unit. Plug the CONTACT Unit into the
430-Mother Unit. Connect the
to the antenna jack, and 8-Q d
SIN AD meter to the
D Tune the transceiver and the
on the band center and inject a signal modulated with
±3.5 kHz deviation of a 1-kHz tone.
Adjust
0
TC3002-TC3005
(at least -8dBµ for 12 dB SINAD). This complete
the first part of the alignment, re-assemble the
transceiver and proceed to the
Alignment Routine.
Internal System Alignment Routine
The remainder of the alignment uses a routine
programmed in the transceiver. This routine simpli­
fies many previously complex discrete component
settings and adjustments with digitally-controlled
settings via front panel buttons and LCD indications.
Transceiver adjustments include:
Band & IF Selection
•
S-Meter Full Scale
•
Squelch Threshold
•
Modulation (Low
•
D To begin, set the transceiver to the VHF and UHF
band center, then turn the transceiver off. Next,
press and hold
powering the radio again. The display now shows
the first setting.
adjustable and are left as set from the factory.
DIAL
In the alignment, each adjustment is selected by
rotating the
holding the @0 key for
injecting a signal of the required frequency and level.
Pressing @0 after a level setting or adjustment is
made stores the entry. To exit the alignment routine,
press After performing the system alignment in
it's entirety, individual settings can be returned to and
adjusted should the need arise.
umm
RF signal generator
y load and
jack.
EAR
RF signal generator to
for optimum 12 dB SIN AD
Internal S y stem
(non-adjustable)
& S-1 Adjustment
& Tight Adjustment
High) Adjust
&
v�/�'
and together while
Note that the first two settings are not
knob. Alignment is performed by
second (U
1h
blinks),
& 430-
then
2-9