Reference Signal Generator Of The Transmitter And Receiver Block - Kenwood TS-990S Service Manual

TS-990S
a 62.4MHz.
The harmonic components are cut by the BPF from the
62.4MHz, amplifi ed by Q57, and output as an SLO2.
The diode switch (D52) cuts the output of SLO2 if IFB is
selected.
IC11
Q3
DDS
AMP
CN66
FMOD
Q4
AMP
Q1
CN42
R40M
40M
Buffer
Fig. 4 Reference signal generator of the transmitter and receiver block, TLO1/SLO1/SLO2/SLO3
8
CIRCUIT DESCRIPTION
Q20 Q28 Q29
D11
Buffer AMP Buffer
FM MOD
Phase MOD
IC10 Q16 IC14
Q23
PLL DDS
393.6M AMP
Q11
AMP
IC1 X1,Q13 Q19 Q25 Q34
PLL
15.6M
Buffer Buffer Doubler
Q2
AMP
■ SLO3 (3rd Local Oscillator for Sub Receiver)
The DDS (IC12) generates an SLO3 which is used for
the modulator and detector.
The DDS outputs the signal via the BPF as an SLO3.
Q17, Q18, Q39, Q40
IC16
CF1
73.125~
Q49
87.755MHz
PLL
AMP
87.755~
103.505MHz
Q60
AMP
D36 D53
D25
D26 D54
D27 D55
D22
D19
IC15
D23
D16
AMP
Doubler
Q50,52
Q57
D52
Doubler Buffer
IC12
Q5
DDS
Buffer
103.505~ Q51 Q56
120.94MHz
AMP AMP
120.94~
133.095MHz
D56
D32
D44
D33
D45
D34 D46
Q61
AMP
CN59
TLO1
CN63
SLO1
CN65
SLO2
CN64
SLO3