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freecell, in the strictest sense there is no such thing as the RMS value of a Power signal, but rather RMS Power describes the metrics used in the calculations. The terms Average and RMS on the meters describe how the voltages or currents are calculated. Average meters rectify the signal and...

As for ground loops, the signal to noise ratio deteriorates due to differences in potential at the various daisy chained gound connections which causes the noise to be magnified as it travels through all of the connections back to the source. This may also cause positive feedback/oscillations...

Toll_Free, you are wrong on both cases. A balanced transmission system has the exact same signals traveling down the wires, 180 degrees out of phase with each other, in opposite directions. This is not the case with 50 ohm coax that is grounded at each end. If there is a different ground...

If you look at my other post you will see that the modulation index can be used for calculating PEP and RMS/Average Power to show how they are related. However, PEP can be calculated directly from the modulated envelope if the RMS/Average Power is not desired. As for the RMS comments...

With a two tone test signal, the SSB PEP can be directly calculated into an equivalent RMS power.

From: 47CFR73.51; "Determining operating power. (a) Except in those circumstances described in paragraph (d) of this section, the operating power shall be determined by the direct method. The direct method consists of either: (1) using a suitable instrument for determining the...

Will you explain this part of your quote? It is much easier to make a fairly accurate Peak meter, while a true RMS/Average power meter is more difficult to design due to the fast rate of change in energy, but there is only one measure of power and it is the amount of energy...

Beetle you are probably right. However, I would like to know what happened after the test procedures in the other thread I suggested were tried. having this data would make possible solutions so much easier... :?

So the noise is radiated and coming from the coax? The 10k is an unbalanced antenna and so is the coax, so a Balun (balanced-to-unbalanced) won't accomplish getting rid of the common mode currents. Try re-tuning and grounding the antenna, or as a last resort, use some ferrite beads on the...

Doc, that is a different answer than coax has no effect, and I agree. Coax will "always" exhibit a different impedance at differing electrical wavelengths when impedances are not exact so tuning of the antenna will nearly always be affected by coax length. As a side note, VSWR says...

Get yourself a good, calibrated, power meter and calculate VSWR using Forward (Pf) and Relected (Pr) Power. The equation is: VSWR = (1 + (Pr/Pf)^0.5) / (1 - (Pr/Pf)^0.5) This will almost always be more consistant, and more accurate, than the majority of SWR meters on the market.

Doc, I don't think anyone will argue that when all impedances are matched, such as when connected to a dummy load, the coax can be any length or velocity factor. Typically what happens is that an antenna is installed at a location that makes the installation easy and not what is best for...

I agree with Bob85. Since the original installation VSWR was not 1:1, meaning the antenna feedpoint impedance is not purily 50 ohms resistive, then the coax will exhibit varying impedance properties as a function of its electrical wavelength. So when a different length and different velocity...

If you key up the entire system when the antenna is removed and it is connected to a dummy load, do you still have a problem? If not, the antenna is causing the problem so try relocating the antenna and see if you can reduce the magnetic fields the sensor is coupling with. If so, then...

Well technically the person you quoted is correct since there are many variables that can be included in any model and tweeked for "1" specific case. But to be honest, engineering is about creating a mathematical model of a system output that will give relatively accurate results for known...

The electric field strength of a ground wave signal is a function of the transmitting antenna current and distance from it. So if you know these values, or can estimate signal strength from an equation, and you pick a baseline receiver sensitivity, you should be good to go. Electric Field...

I agree that using good coax is paramount. The dB rating listed as a specification is for a VSWR of 1:1. So if the antenna feedpoint impedance is not ideal (matched) then the dB losses will be more. These losses will increase at some proportionality constant with the square of the standing...

Here are the FCC rules requiring licenses. http://wireless.fcc.gov/commoperators/wncol.html And while a license may not be required for all areas of rdio communications, I am sure many employers will not hire a technician without some sort of credential.

When I took the test back in the early 80's, they had just merged the 1st and 2nd Class radiotelephone licenses into the General Class License. Back then it was "all" tubes, even for the RADAR endorsement, which was great for working with high power transmitters... :)

Beetle, actually my explanation does, I just need to try and explain it a little differently. :) The currents, or magnetic fields, existing between the center conductor and shield inside the coax are shuffled back and forth within a limited distance inside the coax. Imagine an RF...