Agilent Technologies Agilent 33500 Series Operating And Service Manual page 126

External Timebase Reference
The external timebase reference provides rear panel connectors (10 MHz In and 10 MHz Out) and circuitry to allow
synchronization between multiple instruments or to an external 10 MHz clock signal. You can also set the phase offset
of the output waveform from the front panel or over the remote interface.
To align the phase of two instruments, use a dual-channel oscilloscope to compare the output signals:
1. Connect the two instruments, with 10 MHz Out connected to 10 MHz In. Use the instrument with the more pre-
cise timebase as the 10 MHz reference output source.
2. Connect instrument outputs to scope channel inputs:
3. Set the same frequency on both instruments. The scope should show the signals to be in sync with regard
frequency, but not phase. (A square wave works well to show the phase difference.)
4. For two-channel instruments, phase sync the two channels to each other. This also synchronizes each channel's
modulating waveforms to the carrier.
Front panel:
SCPI: [SOURce[1|2]:]PHASe:SYNChronize
5. Leaving the phase setting at its default (zero) on the first instrument, use Adjust Phase to adjust the phase of
the second instrument to align the output signals:
Agilent 33500 Series Operating and Service Guide
External Timebase Reference
125