TIGHAR
Amelia Earhart Search Forum => Radio Reflections => Topic started by: Tom Bryant on June 10, 2012, 05:24:08 PM
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Sorry if this has already been covered elsewhere - I am still wading through all the data and ideas here and have not found this covered yet. Decided to beg forgiveness and take this shortcut.
In reference to the potentially broken antenna at takeoff.
Would this have any impact on AE's ability to transmit and receive based on her orientation to the listener? Using radio tracking for instance I have used the antenna orientation to null out the signal to get my direction. I do it based on instructions and not on any great knowledge of radio theory LOL.
I do not have the radio tech to know if breaking that antenna could create a situation where as long as she was facing Howland she had contact but once turned on the north south heading have contact compromised for range and or readability?
As another question for the radio experts, and once again from my own experience having signals attenuated due to salt water contact, would the trailing end of a broken antenna either in the salt water or against salty wet sand or being washed by surf cause issues with transmit and receive.
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Tom, welcome to the Forum.
Below is a link to an article that explains the problems with communications that AE had and an explaination of why they occured. Some of the information is complicated and there are many references before everything is presented.
Have fun reading.
http://tighar.org/wiki/Failure_to_communicate (http://tighar.org/wiki/Failure_to_communicate)
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In reference to the potentially broken antenna at takeoff.
Would this have any impact on AE's ability to transmit and receive based on her orientation to the listener?
The question of the purpose of the (ventral) antenna has been kicked around in the old Forum.
The top (dorsal) antenna (http://tighar.org/wiki/NR16020_antennas) seems to have been designed for transmission.
Joe Gurr's modifications (http://tighar.org/wiki/NR16020_antennas#Gurr.27s_modifications) may have crippled the antenna. He tried to get it to resonate on 500 kcs, 3105 kcs, and 6210 kcs. People disagree on exactly what he did to the antenna and what the effect of his modifications would be.
If the top antenna was used solely to transmit and the bottom antenna solely to receive, loss of the bottom antenna shouldn't have affected the transmission pattern.
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So many darned ifs - but that's what makes it interesting.
I was curious about the salt water because of an experience I had many moons ago with tracking collar work. Every time a beastie would encounter salt water the signal was gone and there were warnings about that all the time. Later in life I had a similar issue with a radio tracking signal from a downed rocket so was curious if having the lower antenna submerged would compromise things.