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<snip> PFC correction on loads >70W but smaller than, say, a few kVA, was driven in a lot of cases by the problem with neutral currents on 3phase Y office loads. All those switching power supplies

Yes, PFC is an issue at 60hz. Just one nit to pick: An inductive or capacitive load is still linear, it does not generate harmonics. All it does is cause the current through the device to be out of

Some excellent points, Jim! Let me take this concept of reflected power to something we are all more familiar with: The AC power sockets in our walls. Whether its 120 vrms, 220 vrms, 308 vrms, 408

< 1/2 Watt is typical. https://www.fairviewmicrowave.com/male-sma-terminations-category.aspx the ones with a "hat" might be rated higher (1 or 2W) but probably not. You really don't want to overheat a

Heed the cautions, or you will be without cal. standards!!! 2-watt carbon comp. or thick film resistors are pretty good for the purpose through 50 MHz (I just checked with the VNA). They are available

It could reflect back from the transmitter toward the antenna (and some be lost in the transmission line) - bouncing back and forth. Don't forget that most transmitters do not have a 50 ohm resistive

Hi Jerry, There is matching the feedline to the antenna and matching the feedline to the transmitter. Only if the antenna comes all the way to the transmitter does the box in the shack match the

Matching circuit as part of the *system* consisting of the antenna, transmission, and matching network is quite acceptable so long as we realize there is no antenna "tuning" involved. With that

Jerry, I second your statements! I agree that "match" is more appropriate in this context then "tune", but "antenna tuner" rolls off a tong easier then an "antenna matcher" :) To some extent, "tuner"

Yes, it doesn't matter the power used for the calibration. You just have to be sure of the resistance value. Un saludo

As Larry says, 5W into your calibration standard would be a really bad idea. If in the US, buy a couple Xicon 283-100-RC from Mouser, use two in parallel for a 50 ohm load, will dissipate 6W all day

Rahul, NEVER use the calibration parts that came with the nanovna for anything other than to calibrate the nanovna with!! The 50 ohm calibration load has the equivalent of about a 1/16W precision

Can I use it for a 5 W radio to calibrate it?

Dave, I agree with you that the antenna itself need not be resonant. Though I'd say that when an antenna tuner creates a suitable matching network for that non-resonant antenna, we can properly say

I have both the first and second editions of J. D. Kraus's book, "*ANTENNAS*". Either edition is likely the best book on antennas that isn't 'big time' heavy in math, although a working knowledge of

For those of you who would like to use the resistive pad to match 75 ohms to the 50 ohm nanovna, the series resistor is 25 x sqrt of 3 (about 43.3 ohms) and the shunt resistor on the 50 ohm side is 50

Other than the name, "ANTENNA TUNER", why is the 'conventional knowledge' so prevalent that the "ANTENNA TUNER" actually "tunes" the antenna. *IT DOES N O T !!!!!* It functions ONLY AS A MATCHING

I assume the book you are referring to is "Antennas" by John D Kraus. Jim mentioned it here: /g/nanovna-users/message/16645 FIrst edition printed in 1950, second edition (with Ronald

No, I mean to create a parallel LC-circuit: the inductor will be parallel to the series connection of the C32 and C33 (tapped to the ground in their middle but this does not matter). That LC-circuit

Thanks for the book link. I just downloaded it and read the first few pages, it will be a good read. Dallas N5fee