Adjusting Reference Oscillator Bandwidth (Option Unr/Unx/Uny); Adjusting Reference Oscillator Band Width (Option Unr/Unx/Uny); To Select The Reference Oscillator Bandwidth; To Restore Factory Default Settings - Keysight E8267D User Manual

Optimizing Performance

Adjusting Reference Oscillator Bandwidth (Option UNR/UNX/UNY)

Adjusting Reference Oscillator Bandwidth (Option UNR/UNX/UNY)
The reference oscillator bandwidth (sometimes referred to as loop bandwidth)
in signal generators with Option UNR/UNX/UNY (improved close–in phase
noise <1 kHz) is adjustable in fixed steps for either an internal or external
10 MHz frequency reference. The reference oscillator bandwidth can be set to
25, 55, 125, 300, or 650 Hz; models without Option UNR/UNX/UNY have a
fixed reference oscillator bandwidth.
At frequency offsets below approximately 1 kHz, the stability and phase noise
are determined by the internal or external frequency reference. At frequency
offsets above 1 kHz, stability and phase noise are determined by the
synthesizer hardware.
To optimize the overall phase noise of the signal generator for your particular
application, make this adjustment depending on your confidence in the
stability and phase noise of the external or internal reference versus the
synthesizer hardware for various frequency offsets from the carrier.

To Select the Reference Oscillator Bandwidth

When using the internal bandwid th reference:
1. Press Utility > Instrument Ad justments > Reference Oscillator
2. Select the desired bandwidth.
When using an external bandwid th reference:
1. Press Utility > Instrument Ad justments > Reference Oscillator
2. Select the desired bandwidth.

To Restore Factory Default Settings:

Internal Bandwidth: 125 Hz
External Bandwidth: 25 Hz (Option UNR), 650 Hz (Option UNX/UNY)
Press Utility > Instrument Ad justments > Reference Oscillator Ad justment >
Restore Factory Defaults.
Keysight E8357D/67D & E8663D PSG User's Guide
Ad justment > Internal Ref Band wid th.
Ad justment > External Ref Band wid th.
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