Keysight Technologies N5224A, Руководство по обслуживанию

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Keysight N5224A/25A Service Guide 5-11
Theory of Operation
Synthesized Source Group Operation
In bands 11-30, the swept VCO signal is passed through a doubler circuit
where the signal for some bands are sent directly to the output of the
synthesizer board while other bands are passed through another doubler
circuit then to the output of the synthesizer board to produce the output
frequencies listed in Table 5-3 .
The output of the A15 13.5 GHz synthesizer board (the LO synthesizer) is 7.438
MHz higher than the output of the A4 and A17 13.5 GHz synthesizer boards
(the source synthesizers). This is because the output of the A15 13.5 GHz
synthesizer board is routed through the A25 LO multiplier/amplifier 26.5 board
to the A27 and A28 mixer bricks where they are mixed with the test signals to
produce a 7.438 MHz IF signal for each of eight receivers (A–D and R1–R4).
Refer to “A27 and A28 Mixer Bricks” on page 5-22 for a more complete
description.
A5 and A10 26.5 GHz Source Boards
The A10 26.5 GHz source board is included only on 4-port models.
Refer to
Table 5-3 and Figure 5-3 for band numbers and frequencies discussed
here.
In bands 2–9, the A5 and A10 26.5 GHz source boards input signals from the
A4 or A17 13.5 GHz synthesizer board are passed through to both outputs
(main and secondary) unchanged.
For bands 10–15 and 19–23, the input signals are passed directly to the
secondary output or amplified and filtered, then sent to the main output.
For bands 16–18 and 24–30, the input signals are doubled, filtered, and
amplified. The signals for these bands are then either passed directly to the
secondary output or passed through more amplification and filtering and sent
to the main output.
A7, A8, A12, and A13 50 GHz Doubler Boards
The A12 and A13 50 GHz doubler boards are included only on 4-port models.
Refer to
Table 5-3 and Figure 5-3 for band numbers and frequencies discussed
here.
For bands 2–15, the lowband input ports of the A7, A8, A12, and A13 50 GHz
doubler boards receive their signals from the A5 and A10 source module OUT 1
and OUT 2 outputs. These signals are passed through to the doubler board
output unchanged.
For bands 16–30, the highband input ports of the A7 and A12 50 GHz doubler
boards receive their signals from the A5 and A10 source module P4 outputs.
These signals are amplified by the A7 and A12 doubler boards and output via
the highband output ports to the highband input ports on the A8 and A13
doubler boards.