Home |
Search |
Today's Posts |
#11
![]() |
|||
|
|||
![]() Stagger Lee wrote: On 15 Aug 2006 19:40:07 -0700, N9OGL wrote: The power in wattage and the electrical field are not related because a power output in wattage can produce different fields depending on lengh of coax, antenna, antenna height...and your friends in the Office of You can't get around physics, Todd. The power density is directly related to the electric field through an Ohm's law type of relationship, expressed as the square of the r.m.s value of e, divided by the impedance of free space. Once you know the power density, it is a matter of summing that power density over the radiation pattern of the antenna to figure out the total radiated power. Therefore, there *is* a relationship between radiated power and field strength. In the case of an isotropic radiator, the relationship between radiated power and field strength is easy to calculate, and it provides one with a limiting case which can act as a guideline. engineering and technology at the FCC will tell you that. The antenna I'm using is a very imefficient antenna, in fact the signal is acually I'm not interested in your rationalizations, Todd, because I'm not the one who is at risk. In this real world, your power output is about five orders of magnitude larger than the power theoretically needed to produce the maximum allowed electric field. To me, that would be a cause for great concern. If you want to risk an FCC enforcement action against you, be my guest. ==================== God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and then there was light. I would really suggest you read the FCC Office of Engineering and technology bulletin on PART 15, it OET Bulletin 63 http://www.fcc.gov/Bureaus/Engineeri...3/oet63rev.pdf expecially page 29 which states: What is the relationship between "microvolts per meter" and Watts? Watts are the units used to describe the amount of power generated by a transmitter. Microvolts per meter (µV/m) are the units used to describe the strength of an electric field created by the operation of a transmitter. A particular transmitter that generates a constant level of power (Watts) can produce electric fields of different strengths (µV/m) depending on, among other things, the type of transmission line and antenna connected to it. Because it is the electric field that causes interference to authorized radio communications, and since a particular electric field strength does not directly correspond to a particular level of transmitter power, most of the Part 15 emission limits are specified in field strength. So logically if you use a ineffecient antenna and ****ty coax then you can create a low enough field....I'm tell you right now, I Have a field strength meter that reads microvolts, and I check the field ever morning, at it's not at no 30 meters either, it's around 17.5 meters and the electrical field is 1,0000 uV ...So believe what the hell you want I check it every morning and it's 1,000 uV @17.5 meters and at 30 meters it's 0. I would also point out I come from a long line of electricians (my father, my grandfather and my great grandfather) and THEY will back me up. |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
HAMS ACCUSE OMEGA ONE OF PIRACY! | General | |||
Hams ruin welcome at Rose Parade | Policy | |||
Open Letter to K1MAN | Policy | |||
Response to "21st Century" Part One (Code Test) | Policy | |||
Response to "21st Century" Part Two (Communicator License) | Policy |