30-11-2012, 05:38 PM
LABORATORY MANUAL
[attachment=41971]
Measurement of Guide Wavelength:
Set the source to a CW frequency in the above range, and measure the frequency with the frequency counter or wavemeter. Do not rely on the scale reading on the sweep generator, as this may not be accurate.
The wavemeter is a tunable resonant cavity, and is used by tuning it until a dip is registered on the SWR meter; the frequency is then read from the scale of the wavemeter. Be sure to detune the wavemeter after frequency measurement to avoid amplitude fluctuations that may occur when the wavemeter is set to the operating frequency.
Place the blank flange on the load end of the slotted line; use two or more screws to get good
contact. Set the attenuator near zero dB. Adjust the SWR sensitivity for a reading near midscale,
WRITE-UP:
Measurement of Guide Wavelength:
Compare the frequencies read on the sweep generator, the wavemeter, and the frequency counter
(if available). Determine the guide wavelength from the measured minima positions; average
your results for different adjacent pairs of minima. Using the measured frequency, calculate the
guide wavelength and compare with the above results. Discuss reasons for discrepancies.
[attachment=41971]
Measurement of Guide Wavelength:
Set the source to a CW frequency in the above range, and measure the frequency with the frequency counter or wavemeter. Do not rely on the scale reading on the sweep generator, as this may not be accurate.
The wavemeter is a tunable resonant cavity, and is used by tuning it until a dip is registered on the SWR meter; the frequency is then read from the scale of the wavemeter. Be sure to detune the wavemeter after frequency measurement to avoid amplitude fluctuations that may occur when the wavemeter is set to the operating frequency.
Place the blank flange on the load end of the slotted line; use two or more screws to get good
contact. Set the attenuator near zero dB. Adjust the SWR sensitivity for a reading near midscale,
WRITE-UP:
Measurement of Guide Wavelength:
Compare the frequencies read on the sweep generator, the wavemeter, and the frequency counter
(if available). Determine the guide wavelength from the measured minima positions; average
your results for different adjacent pairs of minima. Using the measured frequency, calculate the
guide wavelength and compare with the above results. Discuss reasons for discrepancies.