From b5f7de88d57ef8a4e4884ce19a9fc32eca3e616b Mon Sep 17 00:00:00 2001 From: Larry Gadallah Date: Sat, 16 Sep 2023 11:56:43 -0700 Subject: [PATCH] Removing ASCII graphs from Doty post --- _posts/2005-09-15-antenna-guru.md | 113 +----------------------------- 1 file changed, 2 insertions(+), 111 deletions(-) diff --git a/_posts/2005-09-15-antenna-guru.md b/_posts/2005-09-15-antenna-guru.md index ed7681d..359f0b1 100644 --- a/_posts/2005-09-15-antenna-guru.md +++ b/_posts/2005-09-15-antenna-guru.md @@ -533,34 +533,6 @@ article: ![50 ohm mismatch]({{ site.url }}{{ site.baseurl }}/assets/images/doty1.gif) -> -> # -> ########################################################################### -> # ## ## ## -> # # # 10 ## 20 ## 30 -> # # # # # # # -> # # # # # # # -> # # # # # # # -> -5 # # # # # # # -> # # # # # # # -> # # # # # # # -> # # # # # # # -> # # # # # # # -> # # # # # # # -> -10 # # # # ## # ## -> # # # # ### # #### -> # # ### # ###### ### ## -> # # #### ## ## -> # # ##### -> # # -> # # -> -15 # # -> # # -> # # -> # # -> # # -> # -> > > The second graph assumes a matching transformer with a 9:1 impedance > ratio at the feedpoint, presenting the antenna with a load resistance @@ -570,33 +542,6 @@ article: ![450 ohm mismatch]({{ site.url }}{{ site.baseurl }}/assets/images/doty2.gif) -> -> # -> # ####### -> -3 # #### ## -> # ## ## ## -> # ## # # -> # ##### # ## # -> -4 # ## ## # # # -> # # # # ## ## -> # # # # #### -> # # # # -> -5 # # # # -> # # ## # -> # # #### -> # # -> -6 # # -> # # -> # # -> # # -> # # -> -7 # # -> # # -> # # -> ############################################################################ -> # # -> # # 5 10 15 20 25 30 -> # # > > Well, so what? In the absence of interference, the signal to noise > ratio is the main determining factor for the audio quality of the @@ -616,34 +561,6 @@ article: ![50 ohm SNR losses]({{ site.url }}{{ site.baseurl }}/assets/images/doty3.gif) -> -> # -> ############################################################################ -> # ## ## #### -> # 5 ## 10 # 15 20 ## 30 -> # ### # # ### -> # ## # # # # -> -1 # # # # # # -> # ###### # # # -> # ## # # # -> # # # # -> # # # # -> -2 # # # # -> # # # # -> # ## # # -> # # # # -> # # # # -> -3 # ## ## # -> # #### # -> # # -> # # -> # # -> -4 # # -> # # -> # ## -> # # -> -5 # -> > > Losses in signal to noise of 3-5 dB are likely to be noticeable. > The largest impact is in the quiet bands above 15 MHz. @@ -651,35 +568,9 @@ article: > On the other hand: the loss in signal to noise with a 450 ohm feed > is much smaller: > + ![450 ohm SNR losses]({{ site.url }}{{ site.baseurl }}/assets/images/doty4.gif) -> -> # -> ########################################################################## -> # ########### -> # 5 ####10 15 20 25 30 -> # ## -> -0.2 # ### -> # ## -> # # -> # ########## -> -0.4 # ### -> # # -> # ### -> # # -> -0.6 # # -> # # -> # # -> # # -> -0.8 # # -> # # -> # ## ### -> # ##### ### -> -1 # ## ### -> # # -> # # -> # # -> -1.2 -> + > > You are unlikely to be able to notice losses in signal to noise in > this range.