Technical data

5-10 Service Guide N5230-90025
Theory of Operation PNA Series Microwave Network Analyzers
Synthesized Source Group Operation N5230C
A10 Frequency Reference Board
This assembly provides stable reference frequencies to the rest of the instrument. A high stability 10 MHz
oven-controlled crystal oscillator (OCXO) normally provides the frequency standard. However, if a 10 MHz
external reference signal is detected at the 10 MHz EXT REF IN port on the rear panel, it is used as the
frequency reference instead.
The 10 MHz reference signal is used to phase lock a 100 MHz VCO. The output of this VCO is then divided by
ten to produce the 10 MHz EXT REF OUT rear panel signal. This 10 MHz signal is divided by two to produce 5
MHz reference signals for the A5 signal processing ADC module (SPAM) board, the A7 fractional-N
synthesizer board, and the A9 fractional-N synthesizer board.
Rear-Panel Interconnects
10 MHz REF. INPUT A BNC connector that allows an external frequency reference signal to be used
to phase lock the analyzer for increased frequency accuracy.
The analyzer automatically enables the external frequency reference feature
when a signal is connected to this input. When the signal is removed, the
analyzer automatically switches back to its internal frequency reference.
10 MHz REF. OUTPUT A BNC connector that allows a 10 MHz reference signal, produced by the A10
frequency reference board, to be output for use in phase locking external test
equipment.