HP 8753E manual Smith Chart Format, Group Delay Format

15 Jun 1994 15:05:13

CHl S,, delay 10 ns, REF 0 s

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16

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STFlRT 75.000 000 MHz STOP 175 000 000 MHz

Figure 6-13. Group Delay Format

Smith Chart Format

I: :..: .....:<<::<ri:”,,::::,:,:.:.:.:.:.:_:.:.:.:.:.:.:.:....

me ;~~,~~~~T softkey &plays a Smith &a& fom-&(see Figure 6-14). This is used

in reflection measurements to provide a readout of the data in terms of impedance. The intersecting dotted lines on the Smith chart represent constant resistance and constant reactance values, normalized to the characteristic impedance, ZO, of the system. Reactance values in the upper half of the Smith chart circle are positive (inductive) reactance, and those in the lower half of the circle are negative (capacitive) reactance. The default marker readout is in ohms (Q) to measure resistance and reactance (R+jX). Additional marker types are available in the Smith marker menu.

The Smith chart is most easily understood with a full scale value of 1.0. If the scale per division is less than 0.2, the format switches automatically to polar

If the characteristic impedance of the system is not 50		ohms, modify the impedance value
_	;). ..,.,.,. ~ ,,,

recognized by the analyzer by pressing (ETJ ~J!##l& ~~~~~ (the impedance value) @.

An inverted Smith chart format for admittance measurements (Figure 6-14) is also available.
	.,..,... ; i .._. .,.,.. ,.,..,.,,.,.; _._/ ._ ;. ..	,.,.,.,. .
Access this by selecting ~~~~~~~~ m the format menu, and pressing CMarker)
,.:.:...:.:. /. : i:. .) .<:. :.~.:.:.:.~~.:;~...:.: .:.:.:.:.:~.:~~.:.:.:.:.:.:.:.:.:.:.:.:.:.~:.:.:.:.:~.:.:.:..: ,.;: _	....................... . . ..:::::
~~~~~~~ ~~~~~~~~ ~~~~:~~~~. me Smith &a is inverted ad maker values
,..._.........................: ./ .:::::::,..~...................../ ,, ~,,.......i::;T::::;:~.......~..*.~, .:::.. ;;:;;<;..;.;,; ;;,.~~/ ......;;...;;;:;;.;;>;:;;;	................ .:;::.i;.i.....:,.,.:,~..,.,...,.i::..::,.,.......:.. .:,.::	....... ::::... ,.;.::..:,.,...::.._...:. ,::

are read out in siemens (S) to measure conductance and susceptance (G+jB).

6.34Application and Operation Concepts