Multi Wire Antennas, early 20th century
Recently I've seen some pictures of bugs and sounders from the middle days of wired telegraphy. And that got me looking at an early wireless telegraphy book:
https://worldradiohistory.com/BOOKSHELF-ARH/Technolgy-Early/Wireless-Telegraphy-and-Telephony-Morgan-1920.pdf
Before proceeding, I thought this dedication was interesting:
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One thing that struck me were the drawings and pictures of multi-wire antennas. The first drawing of a transmitter shows an antenna with multiple wires and that "fan" connection that probably gave rise to the antenna symbol used in schematic drawings.
Here is a photo of an amateur antenna and shack:
This all reminded me of that famous Sarnoff/Einstein/Steinmetz photo mentioned previously in the blog:
https://wb9kzy.blogspot.com/2022/06/famous-people-meeting-or-not-plus-ultra.html
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| Sarnof, Einstein and Steinmetz |
The tangle of stuff above the heads of the group appears to be the terminus of a mighty multi-wire antenna used by RCA to communicate with Europe.
The Morgan wireless book doesn't really go into why the multi-wire antennas were used, it's just assumed, like the current LSB / USB band convention.
Finally I did find this paragraph in the 1929 ARRL handbook:
Perhaps as hams moved up in frequency they found they didn't need the extra capacitance since the antennas weren't as electrically short as they were in the first decade of the 20th century.
Anyway, it couldn't be fashion, had to be the economic / electrical / mechanical realities that drove the single wire antennas.
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm