Comtech EF Data KST-12025 - Manual (Page 98)

Theory of Operation KST-12025 Ku-Band Satellite Terminal
5–12 Rev. 1
5.3 IF Local Oscillator
The IFLO contains a Voltage Controlled Oscillator (VCO), loop filter, and a divide
down chain.
The loop tracking voltage is sent to the M&C board, where it is monitored along with the
lock detect fault.
Refer to Figure 5-5 for a block diagram of the IFLO.
5.3.1 Specifications
Input 10 MHz square wave, CMOS levels
Output 1150 MHz (2 each), 2300 MHz (2 each)
Connectors SMA
Output Impedance 50
Ω
Output level +7 dBm (-4 dBm, U/C Synth Reference)
IF L O C A L O S C IL L A T O R
1 0 M H z R E F E R E N C E
U /C S Y N T H R E F
D /C S Y N T H R E F
D / C I F L O
F IL T E R
U /C I F L O
S M A F E M A L E
C M O S L E V E L S
S Q U A R E W AV E
2 3 0 0 M H z
S M A F E M A L E
+ 7 d B m
2 3 0 0 M H z
S M A F E M A L E
+ 7 d B m
11 5 0 M H z
S M A F E M A L E
+ 7 d B m
11 5 0 M H z
S M A F E M A L E
+ 7 d B m
L O O P
F I L T E R
P H A S E
D E T E C T
V C O
D I V I D E
D O W N
C H A I N
Figure 5-5. IF LO Block Diagram