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Old August 19th 06, 12:26 AM posted to rec.radio.amateur.policy,rec.radio.amateur.misc,alt.radio.pirate,rec.radio.shortwave
Slow Code Slow Code is offline
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First recorded activity by RadioBanter: Jul 2006
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Default N9OGL: Exceeding the Part 15 EM limitation for fun and profit

wrote in
oups.com:


Slow code wrote:
Saggytits Lee wrote in
:

On 15 Aug 2006 10:32:49 -0700, N9OGL wrote:

Steve the Electrical Field emission for 13 Mhz is 15,484 uV/m @ 30
Meters. Omega One Radio is running a power output 100 watts, and the
electrical field emission a 17.5 meters is 2,000 uV. At 30 Meters
the field emissions is 0 uV You Also have to remeber that 13 MHz
is the 22 meter Shortwave Band, which does skip. It it possible to
hear part 15 stations on that frequency. You can put out a higher
power and produce the required electrical field.


A back of the envelope calculation says you are way over the legal
field strength if you're running 100 watts. You can calculate the
power it takes for an isotropic radiator to produce a field strength
of 15,484E-6 volts/meter as follows:

1. The area of a sphere of radius r is 4*Pi*r^2. An isotropic
radiator emitting P watts at the center of the sphere will produce a
power density of Pd = P / ( 4*Pi*r^2) on its surface.

2. The power density is related to the electric field and the
impedance of free space (120*Pi) by the formula Pd = e^2 / (120*Pi).

3. Solving (1) and (2) for the power, P, you come up with P = (er)^2
/ 30.

So, for an "e" of 15,484E-6 and an "r" of 30, P = 0.00719 watts, or
roughly seven milliwatts.

Since antennas are not isotropic, the power must be reduced even
further so that the electric field will not exceed the legal limit in
the direction of highest antenna gain.

This calculation ignores line losses and final amplifier
inefficiencies, but there's no way in Glendale you can convince me
that you can take a 100 watt transmitter and manage to lose so much
power that you have seven milliwatts or less being radiated.

All my DeVry Correspondence School instincts tell me that you are
seriously in violation of the law. Other DeVry grads at the FCC will
immediately agree, as will our distinguished alumnus, KC8JBO, the
only man to have discovered negative VSWR.

Be careful, Todd, and rethink your current station configuration.




Maybe Daugherty hired Wiseman to be engineer in chief at OMEGA ONE...


No, dumbass, he ****s it up all by himself, maybe he hired a no code
training wheel ham like Davies.




Did you really soil your underwear when you heard the knock
on the door? I bet that must have really sucked.