Oscillation Frequency On Each Band; 1Lo Pll Vco - Furuno FS-1503 Service Manual

·
C = 1000 pF
·
CR506 to 508 = 1SV232
(Variable capacity diode)
T501 - 504
BAND Select
T
T501 - 504
(L)
C
(Changing capacitance)
Band
1-L
1-H
2-L
2-H
3-L
3-H
4-L
4-H
Note) The above table shows the VCO output frequency on TLX and FAX modes. Add an
offset frequency for other modes.
Reference) PLL1, PLL3, DDS and BAND data are set in the following order every time
set frequency and/or class of emission is changed.
1) DDS data setting
2) PLL1 data setting
3) SYN shift register data setting (1Lo Band data)
4) PLL3 data setting
VCO CONT
Q503
C
12 V
(C1) (C2)
R522
C
C
C
(C3) (C4)
H/L
Figure 2-8 1Lo PLL VCO
Table 2-6 Oscillation Frequency on Each Band
Set Frequency
0.1 to 2.99999 MHz
3.0 to 5.99999 MHz
6.0 to 9.49999 MHz
9.5 to 13.49999 MHz
13.5 to 17.49999 MHz
17.5 to 21.49999 MHz
21.5 to 25.49999 MHz
25.5 to 29.99999 MHz
f =
VCO
2 π
L ×
VCO OUT
(f )
VCO
Note)
· C2, C4 Variable with H/L Signal
· C1, C3 Variable with VCO CONT
VCO Output Frequency
54.55500 to 57.45499 MHz
57.45500 to 60.45499 MHz
60.45500 to 63.95499 MHz
63.95500 to 67.95499 MHz
67.95500 to 71.95499 MHz
71.95500 to 75.95499 MHz
75.95500 to 79.95499 MHz
79.95500 to 84.45499 MHz
2-16
1
(C1 + C2) × (C3 + C4)
(C1 + C2) + (C3 + C4)