Racal Instruments 3162A/B, User Manual

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User Manual 3162A/B
Using The Instrument 3-13
FREQ:HOP:SOURce {EXTernal | TTLTrg<0-3> | ECLTrg0 | DSUB}
selects the hop advance source. EXT selects the front-panel TRIG IN
connector. Every valid trigger signal increments the table to the next step.
TTLT<n> or ECLT0 select the corresponding VXIbus backplane trigger line.
A front-panel D-Sub connector is selected as the hop advance source when the
DSUB option is selected. This connector has 9 pins, of which one (pin 9) is
connected to ground and the other 8 pins are used as advance control lines.
The binary value of these 8 lines determines the next hop step. For example,
when none of the pins are connected to an ex5V signal, the generator
outputs its carrier frequency. If pins 1 and 2 are connected to an ex5V
signal, the output hops to the frequency set by step Hop Table entry number
3.
The query:
FREQ:HOP:SOURce?
queries the hop frequency advance source and returns either EXT, TTLT<n>,
ECLT0 or DSUB.
The command:
FREQ:HOP:DELete<n>
deletes the specified hop steps from the hop table.
The command:
FREQ:HOP:DELete:ALL
deletes all hop steps and resets the hop table.
Selecting the
Reference Oscillator
Use the following command to select the reference oscillator for the
synthesizer circuit:
ROSCillator:SOURce {CLK10 | EXTernal | TCXO}
TCXO is the standard reference oscillator for the Model 3162B. The default
reference oscillator is set to TCXO. Regardless, you can still select and use
other reference sources. CLK10 accuracy is 100ppm and TCXO accuracy is
1ppm. If you have a 10MHz signal that is either more stable or is shared with
other system modules, you can apply it to the front panel reference input.
CLK10 connects the VXIbus backplane clock to the internal synthesizer circuit.
EXT connects the front panel TTLreference input to the main clock circuit.
The query:
ROSCillator:SOURce? {CLK10 | EXTernal | TCXO}