Rohde & Schwarz FS-SNS18 User manual

R&S®FS-SNS
18/26/40/55/67/90/110
Smart Noise Source
Manual
1338805002
Version 06
(=VÞÀ2)

About the R&S®FS-SNS smart noise
sources
R&S®FS-SNS 18/26/40/55/67/90/110
2Manual 1338.8050.02 ─ 06
1 About the R&S®FS-SNS smart noise
sources
The R&S®FS-SNS smart noise sources are especially designed for
Rohde & Schwarz signal and spectrum analyzer families.
This manual applies to the following devices:
Product name Order number
R&S FS-SNS18 1338.8008.18
R&S FS-SNS26 1338.8008.26
R&S FS-SNS40 1338.8008.40
R&S FS-SNS55 1338.8008.55
R&S FS-SNS67 1338.8008.67
R&S FS-SNS90 1338.8008.90
R&S FS-SNS110 1338.8008.11
You no longer have to enter complex ENR tables into the analyzer, or load them
manually via USB stick, thus avoiding errors due to wrong or incomplete tables.
The temperature is set automatically according to internal measurement. Uncer-
tainty calculations are done automatically and can even be displayed in the result
screen.
Key features
●Frequency range up to 18 GHz, 26.5 GHz, 40 GHz, 55 GHz, 67 GHz, 90 GHz
or 110 GHz
●ENR table automatically loaded
●Automatic uncertainty calculation using ENR uncertainty and reflection coeffi-
cients table
●Improved accuracy due to temperature setting

Preparing for use
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2 Preparing for use
The R&S®FS-SNS is designated for use in industrial, administrative, and labora-
tory environments. Use the R&S®FS-SNS only for its designated purpose.
Observe the usage instructions documented in this manual, as well as operating
conditions and performance limits stated in the data sheet. The product documen-
tation helps you use the R&S®FS-SNS safely and efficiently. Keep the product
documentation in a safe place and pass it on to subsequent users.
●Before use, inspect the RF and interface connectors of the R&S®FS-SNS for
damage. If there is any damage, contact Rohde & Schwarz for repair.
●Before use, inspect the R&S®SNSCABLE and R&S®SNSCABLE-Y cables for
damage. If there is any damage, contact Rohde & Schwarz for repair.
●Always use an appropriate torque wrench when connecting the R&S®FS-SNS
cables to an instrument to avoid excessive force.
●Ensure the instrument that you want to connect the R&S®FS-SNS to has an
appropriate RF input connector.
–R&S®FS-SNS18: SMA male
–R&S®FS-SNS26: APC 3.5 mm male (compatible with SMA)
–R&S®FS-SNS40: 2.92 mm male (compatible with SMA)
–R&S®FS-SNS55/67: 1.85 mm male (compatible with 2.4 mm)
–R&S®FS-SNS90: WR12
–R&S®FS-SNS110: WR10
3 Measurement setup
Depending on the available connector types on the analyzer, connect the
R&S®FS-SNS to the instrument as described below.
For sensitive DC-coupled amplifiers, we recommend using a DC blocker.
The identification and setup procedure after connecting the R&S®FS-SNS
can take up to 10 seconds.

Measurement setup
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Setup for Lemosa noise source control connector
For instruments with the Lemosa noise source control connector, use
the SNSCABLE.
Lemosa
Noise
source
control
RF
Input
DUT
in out
SNSCABLE RF cable
Figure 3-1: Setup with SNSCABLE
Setup with BNC connector or Lemosa noise source control connector with-
out middle pin
For instruments with a BNC connector or a Lemosa noise source con-
trol connector without the middle pin, use the SNSCABLE-Y.
BNC
Noise
source
control
RF
Input
USB
DUT
in out
SNSCABLE-Y RF cable
Figure 3-2: Setup with SNSCABLE-Y

Measurement setup
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Adapting waveguide to coax connectors
The R&S®FS-SNS90 and 110 models have waveguide connectors for output. If
the DUT or the other connected devices have a coax connector, an adapter is
required.
RF
Input
DUT
in out
IF IN /
LO
OUT
Waveguide
adapter
Noise source
(e.g. FS-SNS90)
Lemosa
Noise
source
control
Figure 3-3: Setup using a waveguide adapter
Downconverting noise output
The frequency noise source together with the DUT can provide output frequen-
cies that are higher than the connected analyzer can process. In this case, you
have to connect an external mixer between the DUT and the analyzer. To improve
accuracy of the measured signal, connecting an additional preamplifier to the
external mixer is recommended. In this case, the complete measurement setup is
demonstrated in Figure 3-4.

Spare parts
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Lemosa
Noise
source
control
RF
Input
DUT
in out
IF IN /
LO
OUT
Noise source
(e.g. FS-SNS110) Preamplifier
Ext. mixer
(e.g. FS-Z110)
Figure 3-4: Setup using a preamplifier and external mixer
4 Spare parts
Article Order number
DX SNSCABLE 1338.8020.00
DX SNSCABLE-Y 1338.8066.00
© 2022 Rohde & Schwarz GmbH & Co. KG
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Phone: [phone] - 0
Email: [email protected]
Internet: www.rohde-schwarz.com
Subject to change – data without tolerance limits is not binding.
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