Home |
Search |
Today's Posts |
#5
|
|||
|
|||
using an HP 8405A to measure SWR ?
On Sat, 31 Dec 2005 22:12:47 -0800, dansawyeror
wrote: Where are these equations? I have searched the ARRL handbook for Gamma and did not find it. This is also the first reference to rho. I am at my holiday place, and don't have reference manuals here, so I can't give you specific references. I am confident that the main formulas you need will be in both the ARRL Handbook and the ARRL Antenna Handbook (though some versions of the ARRL publications contain an incorrect formula for Gamma / rho). They will be in any text on transmission lines. Because I don't have the Geek font available here, I write Gamma to mean the uppercase Greek symbol gamma (G). Textbooks should use the symbol. "Gamma" (meaning the uppercase Greek Gamma symbol) is the complex reflection coefficient and Gamma=(Zl-Zo)/(Zl+Zo) where Zl and Zo are complex quantities. rho (lowercase Greek rho) is the magnitude of Gamma, rho=|Gamma|. VSWR=(1+rho)/(1-rho). You can rearrange these expressions to suit your needs. For example, Zl=Zo*(1+Gamma)/(1-Gamma). Be careful, there are different notations and meanings in different texts. You need a reference! Owen -- |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
measuring antenna resonance with an 8405a | Antenna | |||
how to measure antenna impedance ? | Antenna | |||
Tape Measure Yagi Antenna Questions | Antenna | |||
How to measure soil constants at HF | Antenna | |||
Measure Z with Vector Voltmeter properly | Antenna |