Agilent Technologies 8935 series e6380a manual Toggles the selection between feet and meters

		Overview of the Test Set’s Built-In Tools
		Using the RF Tools Program
	The greatest accuracy is obtained when you enter a cable length
NOTE
	slightly greater than the cable length begin tested. If you are not sure of
	the cable length, enter a value 1.5 times the estimated length.
	Depending on the return loss of the antenna or device at the end of the
	cable, you may see a high relative mismatch displayed at the actual
	length of the cable. For example, a 50 foot cable was tested to generate
	the plot in Figure 4-18 on page 101.
	4. Position the cursor at Cable length units. Pressing the knob
	toggles the selection between feet and meters.
	5. Position the cursor at Cable class and select it. A Choices menu
	appears allowing selection of Heliax, RG, and custom options. Select
	the appropriate cable class. (They can also be selected by pressing
	k1 (HELIAX), k3 (RG), or k5 (Custom).
	6. The next menu varies depending on Cable class:
	•	If Heliax is selected: Position the cursor at Cable type and
		select. A Choices menu appears with foam, air, and flex of
		varying thickness. Use the knob to select the desired cable type.
	•	If RG is selected: Position the cursor at Cable type with the

example [RG 58/U = 58] and select.

• If Custom is selected:

a. Position the cursor at Cable velocity propagation const

and select it. Enter the appropriate value. Cables that use polyethylene dielectric typically have a propagation velocity of 0.66, cables that use a teflon dielectric typically have a propagation velocity of 0.70. The propagation velocity must be a value between 0 and 1.

b. Position the cursor at Cable atten. dB/100 ft. (or meters) at 500 MHz and select it.

c. If the cable attenuation is unknown, enter 0 dB per 100 feet (or meters). Entering 0 dB/100 will produce return loss values lower than actual, but fault distance can be accurately detected.

7. Press k1 (Begin Tst).

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