Chapter 2 — Functional Description
2-3 Frequency Synthesis
MG3702xA MM
PN: 10370-10372 Rev. B
2-7
Instrument Inputs/Outputs
The A10 rear panel PCBs and the A2 microprocessor PCB contain the interface circuits for the majority of the
rear panel input and output connectors as shown in
and in
Motherboard/Interconnections
The motherboard PCB and associated cables provide the interconnections for the flow of data, signals, and DC
voltages between all internal components and assemblies throughout the MG3702xA.
2-3
Frequency Synthesis
The frequency synthesis subsystem provides phase-lock control of the MG3702xA output frequency. It consists
of three phase-lock loops: the 100MHz loop, the coarse loop and the fine loop. Operating together, the three
phase-lock loops produce an accurately synthesized, low-noise RF output signal. The circuitry is contained
within two PCBs: the A7 Reference Loop and Coarse loop, and the A9 RF Oscillator, Coarse Loop and Fine
Loop). These boards work together to generate an output of 2 to 20 GHz. The following paragraphs describe
phase-lock loops and the overall operation of the frequency synthesis subsystem. See
A7 PCB
The A7 Reference/Coarse Loop module generates the reference frequencies used within the MG3702xA. It
combines the fixed references (10 MHz, 100 MHz and 300 MHz) with a fast switching coarse loop. The coarse
loop section provides coarse frequency steps on the output of the fast switching frequency synthesizer. The two
main parts are the 100 MHz Reference Loop and the Coarse Loop.
100 MHz Reference Loop
The 100 MHz Reference Loop has 3 methods for controlling the 100 MHz heater stabilized crystal
oscillator:
Table 2-2.
Instrument Input/Output Interfaces
Input/Output Connectors Interface
10 MHz REF OUT and 10
MHz REF IN
Routed through the A10 rear panel PCBs and coupled to the A7 Reference/Course
Loop PCB via coaxial cables.
PULSE TRIG IN, PULSE
SYNC OUT and
PULSE VIDEO OUT
Routed through the A10 rear panel PCBs, and then to the A6 ALC PCB via coaxial
cables.
EXT ALC IN,
Routed through the A10 rear panel PCBs, and then to the A6 ALC PCB via a cable
and the mother board.
EXT TRIG and LOCK
STATUS OUT
Routed through the A10 rear panel PCBs, and then to the A4 AUX PCB via a cable
and the mother board.
VGA, ETHERNET, USB
HOST, USB AND SERIAL
Routed through the A10 rear panel PCBs and then through the motherboard to the
A2 microprocessor PCB.
AUXI/O
Routed through the A10 rear panel PCBs and then through the motherboard to the
various PCB.
IEEE-488 GPIB
Routed through the rear panel to the motherboard and then to the A2 microprocessor
PCB.
100 MHz IN and 100 MHz
REF OUT
Routed through from the rear panel to the A7 Reference/Course Loop PCB via
coaxial cables
EFC IN
Routed to the A7 Reference/Course Loop PCB via coaxial cable.
Summary of Contents for MG3702xA Series
Page 4: ......
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Page 8: ...TG 8 PN 10370 10372 Rev B MG3702xA MM ...
Page 24: ...1 12 Test Equipment List Chapter 1 General Information 1 10 PN 10370 10372 Rev B MG3702xA MM ...
Page 42: ...2 5 RF Deck Assemblies Chapter 2 Functional Description 2 18 PN 10370 10372 Rev B MG3702xA MM ...
Page 120: ...5 5 Troubleshooting Tables Chapter 5 Troubleshooting 5 24 PN 10370 10372 Rev B MG3702xA MM ...
Page 182: ...Index 4 PN 10370 10372 Rev B MG3702xA MM ...
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