A7, A8, A12, And A13 50 Ghz Doubler Boards; A56, A57, A58, And A59 70 Ghz Doubler Boards; A25 Multiplier/Amplifier 26.5 Board (Hma26.5); A14 Frequency Reference Board - Keysight N5227A Service Manual

Theory of Operation PNA Series Microwave Network Analyzers
Synthesized Source Group Operation N5227A

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 5-1 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 16–18, 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.
For bands 16–18, the input signals of all four doubler boards are amplified and filtered, then sent to the
doubler board output.
For bands 19–35, the input signals of all four doubler boards are doubled, amplified and filtered, then sent to
the doubler board output.
Doubler board output signals for bands 2–35 create the full synthesized source output frequency range of 10
MHz to 40 GHz.
The A7 50 GHz doubler board provides an EXT TSET DRIVE RF1 OUT signal to the rear panel. This signal is
output at a frequency range of 3.2–19 GHz for use with an external test set. This output is terminated with a
50-ohm load on the A8, A12, and A13 doubler boards.
The companion signal, EXT TEST SET DRIVE LO, is output from the A27 mixer brick. Refer to "A27 and A28
Mixer Bricks" on page 5-25.

A56, A57, A58, and A59 70 GHz Doubler Boards

The 70 GHz doubler boards create the full output frequency range of 10 MHz to 70 GHz by combining two
input signals from the 40 GHz doubler boards.
The first input signals are from the 40 GHz doubler P2 output (bands 39 - 48), where the signals are filtered,
doubled, amplified, and sent to the combiner. The second input signals are from the 40 GHz doubler P6
output (bands 2 - 38), where the signals are passed through the 70 GHz doubler and sent to the combiner.
The forward combiner then combines both signals to create a full range of 10 MHz to 70 GHz output.

A25 Multiplier/Amplifier 26.5 Board (HMA26.5)

In bands 2–15 and 23-26, the synthesized LO input is filtered, amplified, and passed through to the A26
splitter (4-port only). In bands 16-22 and 27-35 , the input is amplified, doubled, and filtered, then sent to the
output.
Together, these signal paths create the full output frequency range of 10 MHz to 26.5 GHz that is sent to the
A26 splitter (4-port only) where the signal is divided and sent to the A27 and A28 (4-port only) mixer bricks
as the LO signal.

A14 Frequency Reference Board

This assembly provides stable reference frequencies to the rest of the instrument. A high stability 10 MHz
oven-controlled crystal oscillator (OCXO) normally provides the frequency standard. However, if a 10 MHz
5-14 Service Guide N5227-90001