>>>> 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).
Well, that would be nice, but somehow, I suspect the grand design of
things in the universe manages to keep other sentient life just out
of reach of mankind. We do know that another similar race with similar
technology is either not interested in us, or is further than 100
light years away.
[...]
 > 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.
OK by me.
 >  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!
What is the gain factor of a large dish antenna?
 >  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.
How 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.
My tests with 4 watts on the best possible terrain (water), resulted
in less than 40 miles. The altitude of the antenna also has a major
bearing on distance. ...Both local altitude, and general altitude
above sea-level affect transmitting distances when line-of-sight is
a factor.
 >  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!
[...] (stuff about various frequencies alloted to hams.)
 > BTW, Hams have talked accross both the Atlantic and Pacific oceans
 > using
 > LESS THAN ONE WATT OUT OF THEIR TRANSMITTERS!
One of the call-signs in my immediate family is KF4ICR (the other I
forget.) ...And I too have talked around the world on 4 watts (11 meter
band, using a super-laser 500 beam antenna on a 80 foot tower).
 > 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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