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Operation Moon Bounce
linuxwrangler writes "Today marks the 50th anniversary of the first transmission of human voice via moon bounce. The voice was that of James Trexler and the technique became an important method of communication for the military that was used until the advent of the communications satellite. It is still a popular activity for ham radio operators."
Laser EME (moonbounce) without using the moon retroreflectors!
73 de F8EJF
Amateur Radio Enthusiasts do CW (morse) communications using moonbounce, not voice. Given the path loss (c.a. 240dB) and power constraints on amateur stations voice is er.. difficult? (Michael: go look at Trexler's antenna spec!)...
More info on "Moon Bounce"
http://www.zetatalk.com/info/tinfo14e.htm
http://www.af9y.com/
John Kerry is a Joke!
Moon bounce isn't something that one can conjure up at will with the flip of a switch. The amateur radio stations doing moonbounce have uber high gain directional antennas and pump 1.5kw (1500 watts), maximum legal power, into them. What you get back is a signal so faint that you then use various pre-amps and notch filtering to pull the signal out of the noise. I was fairly certain moon bounce on ham bands was limited to CW (contious wave aka morse code.) (Morse code takes a very minimal amount of bandwith and thus the power is focused instead of scattered across a large portion of spectrum.) iirc when the government did moonbounce they would pump something more to the order of 500kW.
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send a burst of data to the moon and let it bounce back then retransmit it without storing it. just a loop. You could fit a certain amount of data in the lag. They used it on farther objects to get longer delays. Kind of a strange idea.
It's nothing strange nor is it science ficton, it's called a delay line memory and it was used in early computers
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Funny you should mention that. The first 47 GHz moonbounce echoes have been reported as being observed yesterday. This was done by a Russian (Sergei RW3BP) living in a block of flats in Moscow using a 2.4m offset dish and high power. He had to use DSP techniques to detect his signal.
and in the fifties I read all about it in "The Lost City," a Rick Brant Electronic Adventure, by John Blaine. (Pseudonym of Harold Leland Goodwin). Like Tom Swift, but more up-to-date and nerdier. This is based on many-decade-old recollections, but they end up stranded on a mountain ledge in Tibet with a hand-crank generator. As I recall the book mentions that they need to crank quite hard to power the filaments in the vacuum tubes. It's Morse Code, of course, not voice. I seem to recall that the radio waves are described as being in the radar wavelength range, but it's really been a long time and I'm into very unreliable memory here.
I wish I could remember why they need to go to Tibet to test the equipment. Probably because If They Didn't, There Wouldn't Have Been Any Story.
Rick's father is a dignified scientist. Rick and his father are always accompanied by lovable sidekicks Zircon (?) and, um, can't remember his name exactly, it's not "Chowdah" but something like that--an Indian (not a native American, but a person from India) who speaks amusingly broken English and makes comic errors due to his entire knowledge of the Western world having been obtained from a copy of the World Almanac.
There seems to be quite a bit more about this at this website
"How to Do Nothing," kids activities, back in print!
they obviously had more than one kind of radio on board. The identity and their location was known to everyone concerned, israelis, the ship itself, and other US assets out in the med and elsewhere, along with various international HAMS who were monitoring what they could of the ongoing war taking place. The attack was delibarate, and designed to pin the blame on egypt (best credible analysis, IMO) in order to garner support for more US intervention and support for the israeli side. They went so far as to strafe survivors for hours in an attempt to kill all the witnesses. They didn't suceed, but to this day the attack continues to be excused as an "accident". The implications in todays politics are there, just extrapolate it as to how far a nation would go to get it's way in international affairs. I know this isn't an exact answer to your question with moon bounce radios, I just wanted to interject about radios in general and on the topic you raised of the attack on the Liberty. Here is a brief history of it for anyone:
http://www.wrmea.com/backissues/0693/9306019.htm
June 1993, Page 19
This Month in History
The Assault on the USS Liberty Still Covered Up After 26 Years
By James M. Ennes Jr.
Twenty-six years have passed since that clear day on June 8, 1967 when Israel attacked the USS Liberty with aircraft and torpedo boats, killing 34 young men and wounding 171. The attack in international waters followed over nine hours of close surveillance. Israeli pilots circled the ship at low level 13 times on eight different occasions before attacking. Radio operators in Spain, Lebanon, Germany and aboard the ship itself all heard the pilots reporting to their headquarters that this was an American ship. They attacked anyway. And when the ship failed to sink, the Israeli government concocted an elaborate story to cover the crime.
There is no question that this attack on a U.S. Navy ship was deliberate. This was a coordinated effort involving air, sea, headquarters and commando forces attacking over a long period. It was not the "few rounds of misdirected fire" that Israel would have the world believe. Worse, the Israeli excuse is a gross and detailed fabrication that disagrees entirely with the eyewitness recollections of survivors. Key American leaders call the attack deliberate. More important, eyewitness participants from the Israeli side have told survivors that they knew they were attacking an American ship.
Israeli Pilot Speaks Up
Fifteen years after the attack, an Israeli pilot approached Liberty survivors and then held extensive interviews with former Congressman Paul N. (Pete) McCloskey about his role. According to this senior Israeli lead pilot, he recognized the Liberty as American immediately, so informed his headquarters, and was told to ignore the American flag and continue his attack. He refused to do so and returned to base, where he was arrested.
Later, a dual-citizen Israeli major told survivors that he was in an Israeli war room where he heard that pilot's radio report. The attacking pilots and everyone in the Israeli war room knew that they were attacking an American ship, the major said. He recanted the statement only after he received threatening phone calls from Israel.
The pilot's protests also were heard by radio monitors in the U.S. Embassy in Lebanon. Then-U.S. Ambassador to Lebanon Dwight Porter has confirmed this. Porter told his story to syndicated columnists Rowland Evans and Robert Novak and offered to submit to further questioning by authorities. Unfortunately, no one in the U.S. government has any interest in hearing these first-person accounts of Israeli treachery.
Key members of the Lyndon Johnson administration have long agreed that this attack was no accident. Perhaps most outspoken is former Chairman of the Joint Chiefs of Staff Admiral Thomas Moorer. "I can never accept the claim that this was a mistaken attack," he insists.
Former Secretary of State Dean Rusk is equall