Keysight Technologies N52 Series User's And Service Manual page 66

Service Information
DC Power Board (N5261-60102)
The DC Power board provides connection to the power supply and self
recovering fuses for each millimeter-wave module supply (+12 volt) on the
front panel. The fuses are reset when the N5261/62A is turned off.
Power Supply (0950-4729)
The power supply (0950-4729) coverts the AC line voltages to DC. This is an
automatic line voltage selecting power supply. The AC line voltage (100 to 240
V @ 50/60 Hz) is provided from the line module located on the rear panel.
Isolators (0955-1595)
Isolators are installed in the LO Output RF path for each port. These 10 watt
isolators maximizes the LO power input to the millimeter-wave modules over a
frequency range of 8 to 19 GHz.
LO Preamplifier (5087-7750)
A preamplifier installed in the LO Input path provides a higher RF power level
required for the
LO Amp.
RF and LO ALC Amplifier (5087-7771)
The Mod/Amp has adjustable gain that provides ALC leveling for the front
panel RF and LO Output signals. Adjustments are made on each Mod/Amp to
set the maximum output power to +12.0 or +12.5 dBm (R3). The output of each
amplifier is connected to a coupler, and with a detector for ALC, the mod/amps
provide RF and LO leveling. Each Mod Amp has a Bias board (N5261-60103)
installed on top that provides the power supply connection and circuitry for
setting the gain of the amplifier (R3) and an SMB Input to the modulator.
The ALC function for the LO is always enabled. The ALC function for the RF
sections may be turned off. The test set controller board stores open loop gain
values for the RF sections. These gain values are used by the PNA firmware to
provide a power level of approximately 10 dBm to the mm-wave heads when
the ALC function is off.
Attenuator, 7 dB (0955-0242)
This attenuator is used at the LO Input port to provide a good match and set
the LO Input level for the preamplifier.
Attenuator, 6 dB (0955-0243)
The 6 dB attenuators are used to attenuate the RF and LO power to the ALC
detector to set the RF level for linear operation.
Attenuator, 3 dB (0955-0246)
The 3 dB attenuators are used in the SRC1 or SRC2 Mod/Amp Inputs to
provide a good match and ensure it does not exceed +15 dBm.
Keysight N5261/62A User's & Service Guide
61