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Unfortunately this doesn't present the same source impedance to the amplifier as that of an actual loop. You will obtain a fairly flat amplitude response, but this is just the amplifier and is not

I try to use a 1:1 voltage balun as the input coupler of the small loop amplifier, so that the gain sweep can be performed directly through the NANOVNA, and I will connect a -10db attenuator in series

Dave and Dirk, Loop/ antenna amplifier for small magnetic loop antennas ( for any small antenna ) does not serve as an impedance compensation network unless you use a non - Foster method of impedance

The best way of testing an active loop is in a Crawford Cell but only a few National Labs have big enough cells to take a 1m loop , it also costs a bit to hire. Using a small TX loop close to the RX

Since s11 is a reflective measurement (think return loss) and from the plot, it appears the loop amplifier is more of an impedance compensation/stabilization network. Dave - W?LEV

Hi Dirk I don’t hink Chavdar has done that, atleast not on separate frequencies. I may be wrong. He has set up a transmitter in far field on 160m but that was for testing the delay line phased

Thank you Mike! I found an article about measuring the difference of the mounting height of SMLs using existing signals from 77 kHz to 28 MHz here:

Hi Dirk, They way I have done it in the past whilst trying to optimise loop and loop amplifier setups, was to place a small loop (as small as possible) within the main loop, and feed the small loop

The proper way would be to set up a calibrated test transmitter in the far field zone and sweep its frequency. You can read how LZ1AQ did it on his website. The gain (or more correctly, antenna

Perhaps a silly question: What is the best way to measure the frequency range of an active SRL? I have built a 1m diameter loop with 10mm^2 copper with a NE592 amplifier. First tests show, that it

Joe, Let me add my five cents to your explanation. Any small antennas when their sizes ( either the loop antenna perimeter or the length of dipole antenna ) are physically small, say ten times of

Hi Frederico The losses impact the antenna's efficiency which is a reciprocal thing ie it affects both TX and RX, however on RX we often use very low efficiency antennas, especially when we want a

Hello *VE7VXO.* I have a doubt regarding the losses you mention, which, I understand, are on the transmission with this type of antennas. But, this type of losses like the ones you mention in point 1

"Here is a discussion where the Kraus equation has been found to be incorrect in yielding the loop feedpoint Z." - quoting AA5CT Kraus calculation is not wrong.? The poster has made an unfortunate

Take a look at my project here: /g/loopantennas/files/AF7KR%20projects/Two%20turn%20shielded%20loop It is 100% shielded and 100% balanced (which may make some difference in null

Oh, yes..... I also have a 1-Meter diameter of 0.5" copper tubing loop which is tuned and I occasionally use it for transmitting during the peak of lightning season. The Q is extremely high. 2:1 SWR

Shielded untuned loops are easy to build and far less expensive than buying one ready-made. I have two which I built: 1) A 2-Meter diameter 2" copper pipe with three internal turns and 2) A 0.5-Meter

Hi Fred; It's non-resonant so it acts like the secondary of an air-core transformer. I had a 48" version for LOWFER work (136 and 472 KHz), but really couldn't see enough signal gain to account for

Good morning Bob, Do you possibly have the same design for 100khz - 500khz? Basically I think the only difference would be the wire length and maybe the loop diameter. Thanks Fred - N4CLA

Thanks Steve and Bob !