Anritsu 37 C Series, Operation Manual, Page: 218 / 603

8-9
RECEIVER MODE The Receiver Mode provides three distinct modes of operation:
q
Sweep/Source Lock mode, phase locks the internal source.
q
Synthesizer/Tracking mode, lets the receiver track a 67XXB,
68XXXB, or 69XXXA synthesizer.
q
Set-On mode, lets the VNA operate as a tuned receiver.
Source Lock Mode The Source Lock mode enables the 37XXXC to phase lock to its inter-
nal source.
Tracking Mode In the Tracking Mode, the 37XXXC steers its second local oscillator
frequency and phase signal so as to phase-lock itself to the reference
signal. Typically the source is a synthesizer, since it must be accurate
to better than
±
10 MHz for the 37XXXC to achieve lock. Due to the in-
herent resolution of the 37XXXC, frequency resolution is limited to 1
kHz intervals. If Option 3 is installed frequency resolution is limited
to 1 Hz.
For receive frequencies outside the indicated test set range, the use of
external mixers and a synthesizer is required. Dual Source Control is
required in this case.
Set-on Mode In the Set-On mode, the source lock circuitry of the 37XXXC is com-
pletely by-passed. Reference signals are no longer necessary for sys-
tem operation. This allows all of the 37XXXC samplers to operate over
their full dynamic range. As a result, the source and the 37XXXC must
be locked to the same 10 MHz time base, otherwise coherent detection
is not possible. Only synthesized sources may be used in this mode.
Dual source control is required.
Due to the inherent resolution of the 37XXXC local oscillators, fre-
quency resolution is limited to 1 kHz intervals over the frequency
range of the VNA. If Option 3 is installed, requency resolution is lim-
ited to 1 Hz.
RECEIVER MODE MEASUREMENTS
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