Anritsu Rubidium MG362 1A Series, Maintenance Manual

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Functional Description 2-3 Frequency Synthesis
MG362x1A MM PN: 10370-10386 Rev. B 2-5
2-3 Frequency Synthesis
The frequency synthesis subsystem provides phase-lock control of the MG362x1A output frequency. It consists
of a phase-locking loops that operating together, produce an accurately synthesized, low-noise RF output
signal.
9 kHz to 2.2 GHz Digital Down Converter
The 9 kHz to 2.2 GHz digital down converter assembly provides the digitized frequency control below 2.2 GHz.
During CW or step frequency operations in the 9 kHz 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 9 kHz 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 ALC Module. Digital control signals from the CPU Module are routed through the auxiliary
PCB.
RF Outputs 2.2 GHz to 20 GHz
Refer to the block diagrams of the RF Deck shown in Figure 2-3 on page 2-12 through Figure 2-4 on page 2-13 ,
for the following descriptions. The MG362x1A uses one YIG-tuned oscillator capable of generating RF signals
in the frequency range of 2.2 to 20 GHz.
20 to 43.5 GHz (Model MG36241A)
RF output frequencies of 20 GHz to 43.5 GHz are produced by doubling the 10 GHz to 20 GHz fundamental
frequencies. Phase-lock control of the 10 GHz to 20 GHz fundamental frequencies, accomplished prior to
doubling, ensures precise control of the 20 GHz to 43.5 GHz frequencies to 0.001 Hz resolution.
Table 2-1. Digital Down Converter Frequency Bands
Band Frequency Range (in MHz)
0 8 to 12.5
1 12.5 to 17.5
2 17.5 to 22.5
3 22.5 to 31.25
4 31.25 to 43.75
5 43.75 to 62.5
6 62.5 to 87.5
7 87.5 to 125
8 125 to 175
9 175 to 250
10 250 to 350
11 350 to 500
12 500 to 700
13 700 to 1050
14 1050 to 1500
15 1500 to 2200