[R-390] Skyhighgain Coaxial Cable Consumer Safety Alert
John KA1XC
[email protected]
Thu, 28 Mar 2002 19:32:54 -0500
Actually,
if you change "coax cable" to "Erbium doped fiber optic cable", and make the
applied "bias"
"laser light", you really do get gain!
:^)
John
----- Original Message -----
From: Barry Hauser <[email protected]>
To: Norman Ryan <[email protected]>; R-390 List <[email protected]>
Sent: Thursday, March 28, 2002 7:15 PM
Subject: Re: [R-390] Skyhighgain Coaxial Cable Consumer Safety Alert
> OK, Norm ...
>
> That's the coaxial cable variation on the shaggy dog story (long, long,
long
> joke) about the miracle car.
>
> Had a carburetor that saved 25%, ignition system that save 35%, camshaft
> saved 15%, high efficiency alternator, another 15%, special synthetic
motor
> oil saved yet another 15%, water injection 20% more, etc. etc. Only
problem
> was, when you stopped at a light, you had to turn off the ignition or the
> gas tank would overflow.
>
> Does this coax actually require a transmitter?
>
> Barry
>
>
>
> ----- Original Message -----
> From: "Norman Ryan" <[email protected]>
> To: "R-390 List" <[email protected]>
> Sent: Thursday, March 28, 2002 6:24 PM
> Subject: [R-390] Skyhighgain Coaxial Cable Consumer Safety Alert
>
>
> > Fellow Mavens,
> >
> > Please read and heed the following Consumer Safety Alert:
> >
> > The recent popularity of a new antenna cable called Skyhighgain Coax has
> > created a safety problem for users and a nightmare for firefighters.
> > SHGC was developed theoretically by Tricenters Experimental
> > Laboratories, Inc., as a signal-boosting element for use in radio and
> > television transmission lines. Scientists at TELI discovered that when
> > a bias voltage is applied to the special material used to make SHGC, the
> > effect was incredible. Instead of simply reducing signal loss, the
> > signal strength increased!
> >
> > Amplification of RF signals in the new coaxial transmission cable was
> > actually greater than 3 db (decibels) per meter per meter. (Please read
> > that again.)
> >
> > In laymen's terms, that means that for every 10 centimeters a signal
> > travels through the cable the signal strength doubles! Put 1 Watt of RF
> > energy into one end of a one meter length of SHGC and you get 2 Watts at
> > the other end (assuming you supply the bias voltage, of course). At two
> > meters you get 4 Watts. At three meters the signal strength increases
> > to eight Watts. Doubling the power every meter the total effective
> > power of the signal exceeds 1,000 Watts by the time it has traveled only
> > 10 meters up the line.
> >
> > Now imagine what would happen if you had a 100-meter SHGC cable. (The
> > actual figures are shown below.)
> >
> > In conventional transmission lines there is always some loss of signal
> > depending upon frequency and the electric characterists of the cable.
> > But with SHGC, instead of a loss, you get a gain in signal strength.
> > This is the stuff every radio engineer has dreamed of.
> >
> > But here's the problem: The unwary (and mathematically challenged)
> > average user seems to think that if a short section of SHGC inserted in
> > his transmission line is good, then a longer one is better. If one were
> > to, say, substitute SHGC for the complete run from the radio shack to
> > the top of a tower, the signal would have more energy than the cable (or
> > the antenna) could withstand.
> >
> > Designed to be used in short sections between standard coax and the
> > antenna, SHGC is not currently available, pending the resolution of
> > certain limiting manufacturing capabilities. Some reports have
> > surfaced, however, that a few samples of the hot-pink colored coax have
> > somehow slipped past reality checkpoints and made their way into the
> > Amateur community. Without official spec sheets and installation guides
> > SHGC poses a significant hazard to the uneducated.
> >
> > The following table dramatically illustrates the danger of using too
> > much Skyhighgain Coax in any transmission line:
> >
> > Length of Coax / Power Output
> >
> > 1 meters - 2 Watts
> > 2 meters - 4 Watts
> > 3 meters - 8 Watts
> > 4 meters - 16 Watts
> > 5 meters - 32 Watts
> > 6 meters - 64 Watts
> > 7 meters - 128 Watts
> > 8 meters - 256 Watts
> > 9 meters - 512 Watts
> > 10 meters - 1,024 Watts
> > 11 meters - 2,048 Watts
> > 12 meters - 4,096 Watts
> > 13 meters - 8,192 Watts
> > 14 meters - 16,384 Watts
> > 15 meters - 32,768 Watts
> > 16 meters - 65,536 Watts
> > 17 meters - 131,072 Watts
> > 18 meters - 262,144 Watts
> > 19 meters - 524,288 Watts
> > 20 meters - 1,048,576 Watts
> > 21 meters - 2,097,152 Watts
> > 22 meters - 4,194,304 Watts
> > 23 meters - 8,388,608 Watts
> > 24 meters - 16,777,216 Watts
> > 25 meters - 33,554,432 Watts
> >
> > As you can see, by the time you reach only 20 meters, the signal power
> > has exceeded a million Watts! Assuming your facility's commercial power
> > mains could handle the load, the signal would exceed 30 million Watts at
> > only 25 meters from the transmitter.
> >
> > Of course, most power main breakers would trip long before the million
> > Watt level, but once the signal starts up the transmisison line the peak
> > envelope power (PEP) climbs so fast that there is a possibility that the
> > circuit breakers would either fuse or the electric current would simply
> > jump the breaker's open switch gap and power would continue to increase
> > until the primary main lines evaporated in what could only be described
> > as a bolt of artificial lightning, showering every surrounding structure
> > with hot plasma and sparks.
> >
> > 73...
> > Norman
> > _______________________________________________
> > R-390 mailing list
> > [email protected]
> > http://mailman.qth.net/mailman/listinfo/r-390
> >
> >
>
>
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