User's Manual

TB8100 Calibration Kit User’s Manual Calibrating the Exciter 21
Calibrating the VCO Modulation
This is step three of calibrating the exciter.
Once you have tuned and calibrated the FCL, you should calibrate the VCO
at frequencies across the band.
Equipment ■ Tuning tool
■ Calibration test unit (CTU)
■ Modulation meter
■ RF attenuator (only required if you are using a PA)
Setup
To calibrate the VCO modulation
1. Ensure you are already connected to the reciter.
2. Select the Reciter Calibration tab, and double-click VCO Calibration.
The VCO Calibration Wizard appears.
3. Attach an appropriate Load and Modulation meter to the PA or exciter
output, set the meter to measure the peak deviation, and then click Next.
(If you are using a PA, it will now transmit.)
4. Using the scale in the dialog box to help you, adjust the exciter lock band
trimmer to center the exciter VCO on the sub-band indicated and then
click Next.
5. For each of the seven frequencies shown, adjust the slider until the deviation
shown on the modulation meter is 3000 Hz (peak). When you have
finished, click Next Band.
6. For each sub-band repeat steps 4 and 5.
7. Click Finish. (If you are using a PA, it will now stop transmitting.)
When you have finished calibrating the VCO modulation, the icon on the
Reciter Calibration tab indicates that this task is complete.
You should now adjust the exciter lock band because it was re-tuned several
times during this procedure. This means that the exciter is no longer on the
required frequency.
1 Reciter 3 RF attenuator (only required if using a PA)
2 PA (optional) 4 Modulation meter
1 2
3
4