Introduction; Product Overview; Figure 1-1 Keysight Sns Series Smart Noise Source - Keysight Technologies N4000A SNS Series Operating And Service Manual

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Introduction

Product Overview

This manual contains operating and service information for the Keysight SNS
series smart noise sources, consisting of models; N4000A, N4001A, and N4002A.
The SNS series smart noise source, when commanded "Off" produces RF noise
due to thermal agitation of its RF components at a level appropriate to its physical
temperature. When commanded "On" it still produces this noise and produces
additional noise component, referred to as EXCESS NOISE. These two noise levels
are used to measure the gain and added noise of the device under test, and
consequently, its noise figure.
The Excess Noise Ratio (ENR) for each SNS has been measured at cardinal
frequencies and these frequency/ENR pair values are stored in the SNS's internal
EEPROM. The ENR of the source relates the level of excess noise in dB to the noise
level appropriate to the standard temperature; 296 K. ENR does not include the
"Off" noise component.
Also included in the EEPROM calibration data is the measurement uncertainty and
the complex reflection coefficient in both the "On" and "Off" states for each SNS.
The SNS has a built in thermometer which monitors the ambient temperature.
This value can be transferred to the analyzer and control the setting of the T
value.
All models are provided with a twelve pin connector for power input and data
transfer. The output connector is a male APC-3.5 on the standard noise sources.
Type-N connectors are available as options for the Keysight SNS models N4000A
and N4001A.
Figure 1-1
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Keysight SNS series smart noise source
Keysight N4000/1/2A Operating and Service Manual
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