Chapter 2 — Functional Description
2-5 RF Deck Assemblies
MG3702xA MM
PN: 10370-10372 Rev. B
2-11
RF Signal Flow
The RF signal from the VCO oscillator and Multiplier is routed to the level control circuits located on the
switched filter assembly and then, via PIN switches, to switched low-pass filters. The PIN switch drive current
signals are generated on the A6 ALC PCB and routed to the switch control input on the switched filter
assembly.
The switched low-pass filters provide rejection of the harmonics that are generated by the VCO oscillator and
multiplier. In MG3702xA, the 2 to 20 GHz RF signal from the level control circuits has four filtering paths and
a through path. The four filtering paths are 3.3 GHz, 5.5 GHz, 8.4 GHz, and 13.5 GHz. Signals above 13.5 GHz
are routed via the through path.
To generate RF signals from 0.01GHz to 2 GHz, the MG3702xA couples the RF signal to the digital down
converter. A coupler in the switched filter path provides this RF signal, which is routed through a 8.5 GHz
low-pass filter to connector J3, and then to the digital down converter. The 0.01 to 2 GHz RF signal output from
the down converter is routed to a diplexer which is connected to the output of the switched filter.
After going through the appropriate path, the RF signal is multiplexed by the PIN switches and routed
through a 20 GHz low-pass filter to the switched filter assembly output connector J2. From J2, the RF signal
goes to the input of the directional coupler or to an amplifier if the instrument is fitted with Option 015.
Instruments fitted with option 015 all use a fixed gain amplifier before the directional coupler as shown in
0.01 to 2.2 GHz Digital Down Converter (Option 004)
The 0.01GHz to 2.2 GHz digital down converter assembly maintains the same basic functionality and control
as the 0.01GHz to 2 GHz down converter. During CW or step frequency operations in the 0.01 to 2.2 GHz
frequency range, a 2 to 4.4 GHz RF signal output from J3 of the switched filter assembly goes to the input
connector J1 of the down converter. This signal is then down converted through a series of dividers resulting in
a 0.01 to 2.2 GHz RF signal output.
The resultant RF signal is fed through a series of band-pass filters, then detected, amplified, and coupled out
for use in internal leveling before being routed to the output connector J3. The detected RF sample is routed to
the A6 ALC PCB.
Step Attenuator
The optional step attenuator (option 002) used in the MG3702xA is a 110 dB Mechanical Step Attenuator.
It provides attenuation of the RF output in 10 dB steps. Maximum rated RF output power is reduced. The step
attenuator drive current for Option 002 is supplied by the A6 PCB.
Summary of Contents for MG3702xA Series
Page 4: ......
Page 5: ......
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 ...
Page 183: ......
