ALlGNMENT PROCEDURES
PLL2 VCO
Alignment
Con
trol
Setting
Test
Instrument
Connection
Adjust
Result
OFFNOLUME
control: ON.
Conneet DC SSVM to TP103.
L128
Adjust L128 to 2.4±0.1 volts
SQUELCH control: Fully
See Figure 1. on the DC SSVM. See Table 2.
counterclockwise (CCW).
Select channel 3.
PLL1 VCO
Alignment
Control
Setting
Test
Instrument
Connection
Adjust
Result
OFFNOLUME
control: ON.
Connect DC SSVM to TP102.
L125 1. Select channel 3 and adjust
SQUELCH control: CCW.
See Figure 2. L125 tor 25.5±O.5 volts on
Select channels 3 and 4.
the DC SSVM.
2. Select channel 4 and be sure
the DC SSVM reads 0.8-3.0
volts
(no adjustments
are
necessary for the coil). See
Table 2.
De
SSVM
lbJ
o
TP103
Unit
Under
Test
Jr
Figure
1
DeSSVM
lbJ
o
TP102
Unit
Under
Test
~
Figure
2
Ajustment
of
Coils L125 and L128
Each coil should be adjusted carefully by changing the pitch of the coil little by little by using a non-metallic tuning
tooi as shown in Figure 3.
Squeeze the coil to increase the voltage and stretch the coil to decrease the voltage.
Notes:
;/
Use
--
non-metallic
Coil tuning tooi
SIlIIllI~llIIIlIIlIIllIl~
RF PCB
Figure
3
• Be very careful when doing coil pitch adjustment be-
cause it greatly affects the frequency.
• Secure the coil with glue after alignment. Be sure the
glue is dry and the coil is secured. Also, be sure that the
environmental temperature is normal. Then, repeat VCO
(PLL2 and PLL1) alignments above.
Table 2
CH
Frequency
Voltage
CH3 30 MHz
Voltage at TP103: 2.3-2.5 volts
CH3 30 MHz
Voltage at TP102: 25-26 volts
CH4 760 MHz
Voltage at TP102: 0.8-3.0 volts
-10-
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