KV vs. Frequency Calibration

This adjustment calibrates the sensitivity of the VCO on the A6 Frac-N.

During this adjustment, the VCO is set to a frequency and the tune voltage is measured and saved. The VCO is then set to a second frequency and the tune voltage measured and saved. The sensitivity is calculated by dividing the frequency delta by the difference between the tune voltages.

The VCO sensitivity is determined for frequencies between 500.00000001 MHz and 1000 MHz. The first VCO frequency is 500.00000001 MHz. The VCO tuning voltage at TUNE_ABUS node is switched to the "Sweep Out BNC" and measured using a multimeter. The voltage is stored as Tune_voltage1. The second frequency is determined by adding the delta frequency to the VCO frequency. The tune voltage is measured and stored as Tune_voltage2. Sensitivity is equal to "delta frequency/(Tune_voltage2 - Tune_voltage1)". At VCO frequencies of 600 MHz and greater, the second VCO frequency is determined by subtracting the delta frequency from the VCO frequency. The sensitivity formula changes and is equal to "delta frequency/(Tune_voltage1 - Tune_voltage2)". The change in the formulas is so the VCO is calibrated between 500.00000001 MHz and 1000 MHz.

Test Equipment

Preferred Model

Alternate Model(s)

Digital Voltmeter

3458A Opt 002

 

 

Connections and Setup Procedures

  • All test equipment requires a 30 minute warmup period to ensure accurate performance.

  • In the following test setup, cables are designated as solid lines and direct connections are designated as dashed lines.

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. While performing this adjustment, follow all instructions on the controller display.

 

Setup for KV vs. Frequency Calibration

In Case of Difficulty

If this adjustment fails, perform the following steps in order:

  1. Check the equipment setup (see above). If the setup is incorrect, make the necessary corrections and rerun the adjustment.

  2. If this adjustment fails with the equipment set up properly, refer to the troubleshooting section of the signal generator's service guide. If you do not have a printed copy of the service guide (Option OBW), one is available either on the CD-ROM that came with your signal generator shipment or on the Keysight Website.

  3. If you cannot correct the problem using the troubleshooting procedures in the Service Guide, obtain service from Keysight Technologies. Refer to Contacting Keysight Technologies.