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Author Topic: Dr. Loomis, first radio communications  (Read 9585 times)
WX7G
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« on: August 27, 2010, 03:11:01 PM »

http://jeff560.tripod.com/loomis.html

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KASSY
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« Reply #1 on: September 04, 2010, 09:37:41 AM »

A mix of urban myth, dreaming and a minor charlatan.

Based on a reading of the Mahlon Loomis entry at the Library of Congress website and a bio that I read many years ago (can't recall the name):
...the article you reference claims that "In January 1873, Congress chartered the Loomis Aerial Telegraph Co".  This is a very clear intional alteration of a cut-and-paste.  The actual text on file at the Library of Congress is "In January 1873, Congress declined to charter the Loomis Aerial Telegraph Co."

Reasons cited are that Loomis failed to demonstrate successfully the capability of his apparatus and "intentionally misleading government representatives".

This leads to the second problem.  He claimed to many that he'd performed this experiment in 1866.  However despite the earth-shattering nature of the experiment, he managed to not keep any of the materials.  He never produced a kite or a wire to show people how he'd done it, and there were no witnesses.  His notebooks refer to the experiment and include drawings and figured, but nothing resembling on-site collected data is found...there is no evidence that substantially indicates the experiment actually took place.  After his patent was granted and Congress failed to charter his company, he declined invitations to participate with others to repeat the experiment.

And finally...there is some evidence that he didn't actually grasp either the experiment or theory (the prevailing theory was DC currents conducted through the high-altitude atmosphere), but only the financial potential: his patent, granted in 1872, contains nearly word-for-word identical descriptions of the "apparatus" as a patent granted three months earlier.  Did he copy the earlier man's work?

The legend of Loomis is a good story to put to bed as the exaggerated dreamy view of a charlatan that it is.

Wikipedia has an abbreviated version of this...but largely in agreement with the history that I read some years ago.

- k
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WX7G
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« Reply #2 on: September 04, 2010, 01:32:19 PM »

Loomis's transmitter should work. Charge an electrically floating vertical wire using the vertical electric field gradient above the surface of the ground. Then connect the end to ground. There will be a damped square wave current having a fundamental frequency equal to 4X the wire length. The antenna as the resonant circuit, requiring the same antenna length at the TX and the RX, is what was used in the Boer War wireless apparatus of 1899.

The receiver is the problem. Wikipedia states that the receiver consisted of a spark gap. In the case of an electrically floating wire the wire will charge to a high DC potential and require a rather large spark gap spacing. The few volts induced by the transmitting wire will not be seen as an arc. Did Loomis connect a resistance across the spark gap to keep the DC potential at 0 volts yet arc over when driven by the RF induced voltage? Unless the TX and RX antennas are quite close there will not be enough RF voltage to arc across the spark gap.

Another account of his alledged experiment states that he used a galvanometer as the RF detector. Would a damped square wave current ringing for a few cycles at 1 MHz move a galvanometer?

Boer War Wireless           http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=491790

The full text of this IEEE paper is fascinating.
« Last Edit: September 04, 2010, 01:41:32 PM by DAVE CUTHBERT » Logged
N2EY
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« Reply #3 on: September 06, 2010, 04:12:29 PM »

There are plenty of cases where somebody invented or discovered something long before the usually-accepted date, but failed to turn it into a practical, repeatable system. For example, there was an FET-like device in the 1920s IIRC.

Whether or not Loomis actually did what he claimed, he never went beyond getting a patent and making some claims. Marconi, OTOH, produced real working systems.

Now if you really want to get a discussion going, talk about who built the first high-speed general-purpose Turing-complete electronic digital computer.

73 de Jim, N2EY

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W0BTU
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« Reply #4 on: September 11, 2010, 09:37:53 AM »

I have an old book in my library by Loomis' daughter (Mary Texanna Loomis) that claimed her dad beat Marconi to it by years. Whether he did or not will probably never be proved with any absolute certainty.
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N2EY
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« Reply #5 on: September 11, 2010, 12:40:20 PM »

I have an old book in my library by Loomis' daughter (Mary Texanna Loomis) that claimed her dad beat Marconi to it by years. Whether he did or not will probably never be proved with any absolute certainty.

I think I have the same book!

"Radio Theory and Operating" - mine's the 4th edition.

Even if Mahlon Loomis did what he claimed, he didn't repeat his experiments nor produce a practical system.

Mahlon Loomis was her cousin, not her father, btw.

73 de Jim, N2EY
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W0BTU
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« Reply #6 on: September 12, 2010, 04:21:56 PM »

I think I have the same book! ... Mahlon Loomis was her cousin, not her father, btw.
73 de Jim, N2EY

Hi Jim,

I always thought it was her father. Whatever. Anyway, I enjoy looking at it the book from time to time.
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N2EY
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« Reply #7 on: September 13, 2010, 03:11:57 AM »

I think I have the same book! ... Mahlon Loomis was her cousin, not her father, btw.
73 de Jim, N2EY

Hi Jim,

I always thought it was her father. Whatever. Anyway, I enjoy looking at it the book from time to time.

Hello Mike,

I had to google to find it was her cousin; the book doesn't seem to say.

Yes it's an interesting book; a snapshot of what radio was like then.

I wonder what happened to her radio school?

73 de Jim, N2EY
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K1DA
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« Reply #8 on: September 23, 2010, 09:13:39 AM »

   Interesting that   Alfred Loomis  was instrumental in getting the MIT radiation lab started in the early days of WWII.  A wealthy man who liked to
"tinker".  He is was heavily involved in LORAN development.  Worth a Google. 
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W0BTU
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« Reply #9 on: September 23, 2010, 02:27:30 PM »

  Interesting that   Alfred Loomis  was instrumental in getting the MIT radiation lab started in the early days of WWII.  A wealthy man who liked to
"tinker".  He is was heavily involved in LORAN development.  Worth a Google.  

Thanks for the heads up. I never heard of him. His wikipedia page is a good read. http://en.wikipedia.org/wiki/Alfred_Lee_Loomis
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