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To Martin, Yes this is the measurement circuit. But the problem is not the resonance of the dummy inductance? to be the same as the actual loop,? but the equivalent current source value which is

Hi All, When we introduced the concept of "dummy" areial model the intention was to use an injected test signal for a variety of small active loop antennae ( unshielded and shielded untuned ) as well

Hi Chavdar. Thanks for this note. Just to be clear, is the circuit shown in the photos section an accurate representation of what you are

*Hi All,* *Northon measurement setup* The Norton equivalent circuit is very convenient model for the wideband active loop. In production tests we have the following setup : Signal generator,

Mike, With a respect to your thoghts to ascertain? the common mode rejection by a loop antenna has nothing to do with the introduction of concept -? injection of test signal through?a dummy aerial

Agreed - "Magnetic Loop" is shorthand for current derived signal, E-Probe / Active whip or Dipole, is shorthand for voltage derived signal. But in practice they contain a bit of

Antenna theory doesn't really separate E and M fields. The combined response of the antenna is a function of both, meaning that there is no such thing as "magnetic loop". You are correct that in the

Hi Raphael, I wouldn't read too much into the webpage copyright statement, I used to have something similar, especially after a few companies copied some of my work and built businesses around

Hi Chim-leon Lim, Thank you for sharing your thoughts and practical results on a loop dummy with us. I really appreciate your experiments and find your approach very helpful and informative. I would

Martin and Dave, Thinking about Dave's advice "not go down the analysys paralysis route..." Something else came up on my mind while re-reading Lim's blog "Electronics, RF & Microwave by 9W2LC" where

QUOTE (from Martin): Let's all see if we can jointly find some alternative circuits, that better fulfil the criteria you require. And....... not go down the "analysis paralysis" route. In science

Hi Raphael, I tried to minimise the problems associated with antenna factor, by using a very small (in proportion to wavelength at the highest frequency) energising loop, and fed it via a resistive

Fred, There is a saying: G'd knows the subject excellant, professor - good and a student -satisfactorly... So, you may choose what category applies to you... Raphael

Fred, That is important because professionals by training can respond technically correctly. In my opinion, in engineering? we are dealing with the technological applications based on science.

Martin, I am glad hearing a Man's Talk. In your induced method of measurement S21 of active loop antenna there is a need? to substruct? analythically from the total measured S21 the gain of passive

Agreed, there is a flaw. In my physical attempts to measure an actual loops performance, the S21 is debatable. Depending on the size of the loops, their proximity, orientation and? frequency in

i don't think that's important for the discussion. regards, Fred

All, This is in response to Lim's idea how to implement a proper model of dummy aerial for SMA. His shortcut with this task is how to create a dummy antenna in order to match up Martin's results of

Loudet's model requires a 0R source or ideal voltage source. If the source impedance is higher than 0R, then it does NOT replicate Martin's loop impedance measurement. The Smith chart linked below

Chin-leong Lim, As you know, there are two methods of testing SMA with its antenna receiver: 1. Induced signal method that Martin used having utilized a second transmiting loop to generate a known