Home |
Search |
Today's Posts |
#10
![]() |
|||
|
|||
![]()
Frank Gilliland wrote:
Cecil Moore wrote: But I specifically stated above the Z0 environment was different from 50 ohms. The same type of error happens when one uses a 50 ohm SWR meter in a 75 ohm coaxial line. If that were true then the mere existence of standing waves could render any measurements worthless. Regardless, I did the experiment a long time ago -- take a 50 ohm SWR meter and plug it into a 75 ohm line -- it gives you almost the same measurement (in fact, I didn't see -any- difference at all). Please run it again in the following configuration: Xmtr--1/4WL 75 ohm line--SWR meter--1/4WL 75 ohm line--50 ohm load The SWR meter will read 2.25:1 when the actual SWR is 1.5:1 Xmtr--1/2WL 75 ohm line--SWR meter--1/2WL 75 ohm line--50 ohm load The SWR meter will read 1:1 when the actual SWR is 1.5:1 Any small error you might see is, as I said before, insignificant, especially considering the reason you are measuring SWR in the first place. A 50% error in SWR reading is NOT insignificant. The objective is simply to get the reading as low as practially possible. If you feel the need to quibble about a couple tenths of a point on a ratio then maybe you're spending a little too much time playing with the calculator instead of the antenna. A 50% error in SWR is NOT a couple tenths of a point. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |