R&S SMA100B, User Manual

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Reference Oscillator
R&S
®
SMA100B
175 User Manual 1178.3834.02 ─ 03
7 Reference Oscillator
The R&S SMA100B is equipped with an internal reference oscillator that generates a
reference frequency of 1 GHz. It is used as internal reference source for the synthe-
sizer. Alternatively, you can apply an external reference signal. The R&S SMA100B
can process external reference frequency in the range 1 MHz to 100 MHz and the
1 GHz reference frequency.
Regardless of the used reference source (internal or external), the R&S SMA100B
always outputs the reference frequency at the output connector. You can use it, for
example to synchronize further connected instruments. For an overview of typical test
situations, see
Chapter 7.2, "Using the Reference Frequency for Instruments Synchro-
nization" , on page 175.
The reference oscillator settings are not affected by an instrument preset (PRESET
key or
*RST
) and the "Save/Recall" function. They are reset only by factory preset.
The remote commands required to define these settings are described in Chap-
ter 12.15.11, "SOURce:ROSCillator Subsystem" , on page 442.
7.1 Required Options
R&S SMA100B base unit equipped with the following options:
●
Reference frequencies 1 MHz to 100 MHz (R&S SMAB-K704)
●
Ultra low noise 1 GHz (R&S SMAB-K703)
For more information, see data sheet.
7.2 Using the Reference Frequency for Instruments Syn-
chronization
Test setups with two or more instruments often require that the instruments use a com-
mon reference frequency. Depending on the availability of external reference fre-
quency source and its quality, the instruments are connected and configured in differ-
ent ways.
This section gives an overview of the possible test setups and the related settings. The
following situations are considered:
●
External reference source is not available or the built-in reference oscillator is of
better quality than the external source
(see
"Distributing the internal 10 MHz reference signal to further instruments"
on page 176)
●
Clean external reference source with quality exceeding the quality of the built-in
reference oscillator
(see
"Using external reference source" on page 177)
Using the Reference Frequency for Instruments Synchronization