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3 if local oscillator, 1 specifications – Comtech EF Data CST-5005 User Manual

Page 81

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CST-5005 C-Band Satellite Terminal

Theory of Operation

Rev. 1

5–11

5.3 IF Local Oscillator

The IF local oscillator (IF LO) contains:

Voltage Controlled Oscillator (VCO)

Loop filter

Divide-down chain

The lock detect status is sent to the M&C board, where it is monitored.

Refer to Figure 5-5 for a block diagram of the IF Local oscillator.

IF LOCAL OSCILLATOR

10 MHz REFERENCE

U/C

D/C

1112.5 MHz
SMA FEMALE
+13 dBm

1112.5 MHz
SMA FEMALE
+13 dBm

LOOP

FILTER

PHASE

DETECT

VCO

DIVIDE

DOWN

CHAIN

Figure 5-5. IF Local Oscillator Block Diagram

5.3.1 Specifications

Input

10 MHz Square wave, CMOS levels

Output

1112.5 MHz (2 each)

Connectors

SMA

Output Impedance

50

Output Level

+13 dBm