LinkBack Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
  #11   Report Post  
Old April 15th 09, 11:11 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Dish reflector

Jim Kelley wrote:
So why do you have to go to all that trouble when you want to measure
traveling wave current, but not when you want to measure traveling wave
energy?


When one measures traveling wave energy, one
is measuring an average calculated scalar value
usually forward power minus reflected power or
RMS V*I in a dummy load resistor.

When one is measuring delay, one is measuring
instantaneous traveling wave phase in real time.
Trigger on the zero crossing of the input signal
and measure the delay until the output signal
crosses zero.

That delay measurement doesn't work for standing-
wave current because the zero-crossing on the
input and output occur virtually simultaneously,
i.e. there is no relative phase shift between
input and output or between any two points on a
1/4WL wire monopole.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Dish Network "500" dish with two LNBs Mike Andrews Homebrew 4 February 23rd 07 08:54 PM
Kenwood reflector Kirk Mohror General 0 August 31st 04 01:01 AM
Vet. with a reflector Drbob92031 Antenna 0 November 18th 03 01:42 AM
Reflector for Hammarlund AA5JJ Boatanchors 0 October 22nd 03 04:38 AM
Reflector for Hammarlund AA5JJ Boatanchors 0 October 22nd 03 04:38 AM


All times are GMT +1. The time now is 08:33 AM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017