>>> Part 1 of 2...
 
-=> On 02-01-98  09:50, Jack Sargeant said to Troy H. Cheek,<=-
-=>"About Speculations...,"<=-
-=> On 27 Jan 98, concerning _Speculations_, Jack Sargeant said to
-=> Charles Daniels in UFO:
 
Hi, Jack;
 
You have stumbled into an area qhwew I have a bit of proven expertise.
 
 JS> Even if communication was established tomorrow via radio telescope,
 JS> our reply would take years to arrive on their home world. two-way
 JS> communications would be impossible. A chess game would take longer
 JS> to play than our solar system will last.
 
True, if it were in another part of the galaxy, however if it were one
of our close neighbors, like Alpha Proxima at 4+ light years, it would
"only" take a little over 8 years to get an answer, (or the next move
in the chess game).
 
 TC> That's the ironic thing about establishing the existance of ET
 TC> intelligence by finding a radio signal:  It won't prove that we
 TC> aren't alone in the universe, because odds are that the
 TC> civilization that sent the signal is long, long gone.
 
Again it depends on where the signal came from.  Of course, our society
is capable of destroying all life on the planet in a lot less than 4
years.   :-<
 
 JS> ... Without
 JS> looking in an encyclopedia, we can start with the early Sumarian or
 JS> Egyptian eras and say about 10,000 years to date as written records go.
 JS> Can we safely add anoter 10,000 years?
 
At the rate our sociery is deteriotrating, I wonder if we, (the human
race), will still be around in 100 years, let alone 10,000.   :-<
 
 JS> ...And how far can a radio
 JS> signal travel before the ethers absorb the last weak remainder of
 JS> a broadcast? Our Explorer missions are just now at the outer reaches
 JS> of our own solar system.
 
Yes, and they are using less transmitter power than a flashlight bulb,
and less than a CB (4 watts output).
 
 JS> Could another civilization tens of thousands of light years away
 JS> still detect our radio emissions?
 
Yes, if they have radio telescopes equal to ours.
 
 JS> A distant Pulsar can radiate a signal billions of times stronger than
 JS> the strongest radio signal man has ever broadcast (approx. 200,000
 JS> watts for the strongest radio stations). I don't know what the limits
 JS> are of radio telescopes, but I would guess at about 100,000 watts.
 
ERROR!  A UHF TV station is limited to one million watts (ERP - Effective
Radiated Power), and there are international broadcast transmitters, such
as the ones used by VOA that exceed that power level.
 
 JS> ...And I doubt if a radio telescope has actually been built that
 JS> can transmit at more than a thousand watts.
 
Even if the transmitter FEEDING the radio telescope only puts out 1,000
watts, the antenna has gain, and can focus it into a beam with the
strength, (ERP), of several million watts!
 
 JS> TV stations that transmit
 JS> to satellites for re-broadcast back to earth certainly don't require
 JS> more than a few thousand watts of focused power. ...Maybe even less
 JS> than a thousand watts.
 
Actually, the ground transmitters which feed "the birds" only use around
20 watts to the antenna, and IIRC, the transponders in the "birds" use
about 10 watts to cover the entire U.S.  But the dish antennas that are
used effectively multiply those power levels many times.
 
 JS> (A 4 watt CB radio signal can travel about
 JS> 30 miles under perfect conditions, and a few thousand miles under
 JS> "skip" conditions, where the signal can bounce off one of the
 JS> atmospheric layers.
 
Actually, they are limited by terrain, not distance.  When Sputnik Jr,
the 40-year memorial of the first manmade object in orbit, was
transmitting last year, I heard it with a handi-talkie when it was OVER
1,000 miles away, and it was only transmitting 200 miliwatts: TWO TENTHS
OF ONE WATT!  But I could only hear it when it was above the horizon.
 
 JS> A ham radio operator may use approx. 10 - 1,000
 JS> watts, and transmit anywhere from 2 meters down to 80 meters on the
 JS> radio frequencies alloted to amateur radio.)
 
ERROR!  Ham radio operators have talked accross the Atlantic and Pacific
oceans using ONE TENTH of a watt to their antennas!  Hams have bands
ranging from 160 Meters, (1.8 to 2 MHz) up to literally LIGHT!  The HF
(High Frequency) bands are: 80 Meters, (3.5-4 MHz), 40 Meters, (3.5-4
MHz), 30 Meters, (10.1-10.15 MHz), 20 Meters, (14.0-14.35 MHz - a good
band for talking around the world during the daytime!), 17 Meters,
(18.068-18.168 MHz), 15 Meters, (21-21.45 MHz), 12 Meters, (24.89-24.99
MHz) and 10 Meters, (28.0-29.7 MHz).  VHF bands: 6 Meters, (50-54 MHz),
2 Meters, (144-148 MHz) and 1.25 Meters, (222-225 MHz).  Then there's UHF
bands: 70 CM, (420-450 MHz), 33 CM, (902-928 MHz), 23 CM, (1240-1300 MHz).
Additionally, there are several SHF bands, including 2300-2310, 2390-2450,
3300-3500, 5650-5295 MHz, and 10.0-10.5, 24-24.25, 47-47.2, 75.5-81,
119-120, 142-149 and 241-250 GIGAhertz, and the highest is "Everything
above 300 GHz," which includes light!  (Yes, Hams have used lasers for
communication over paths of several hundred miles!)  And on most of those
frequency bands, there is an almost unlimited number of modes that can be
used, from the origional Morse Code, AM, FM, SSB, Spread Spectrum, data,
(several different modes), TV, FAX, PWM, PPM, and others too numerous too
numerous to mention here... ALL invented and developed by Hams, working
either privately or Govt/Industrial employers!
 
BTW, Hams have talked accross both the Atlantic and Pacific oceans using
LESS THAN ONE WATT OUT OF THEIR TRANSMITTERS!
 
The frequencies below about 50 MHz are used for local and international
communications, the higher frequencies are used for local, satellite,
 
 >>> Continued to next message...
 
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