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If you look at the physics of the "shielded" loop, you will rapidly realize it is NOT SHIELDED from the induced currents! That's the whole reason for the gap at the top high-Z point, opposite the feed

I would agree with Simon. Use an unshielded coupling loop and place an effective common mode choke on the feedline, and also on any control cables. Regards, Martin

OK. . . 90 degree hybrids with mulitoctave frequency are possible but this is the 21st century. . . Buy a dual channel SDR receiver with matching "IF signal handling" chains and create the 90 degree

An addition: As you can see from the phase plot the deviation from 90 deg is less than 5 deg for the range: 2.4 - 37 MHz. The design can be easily scaled to another frequency range. But note: there is

A few years ago, a similar topic appeared in another group: /g/SimSmith/topic/69302617. Last year, Chris Smith NX0E shared his hybrid coupler design with me. He based his design on

Hi Unshielded..been there done it..dont waste time on shielded. Its not the antenna, its just the coupling to the antenna which has already received any noise. A common mode choke in coax by antenna

Hi all and thanks for accept me in the group. I'm building a magnetic loop antenna for TX and I slightly follow the instructions in https://www.nonstopsystems.com/radio/frank_radio_antenna_magloop.htm

I think it is feasible to chose component values that would produce a 90 degree phase shift at a given frequency, especially if this is somewhere close to resonance, and if you are only interested in

Hi Martin and All Illustration of SCPQ-10.5 Datsheet. I thought about the "or some other element" that Martin mentioned. Most simple one is capacitance between the coil. I did a simple simulation in

I will be interested to see how well that performs outside its specified frequency range. I suspect it would actually work OK down to at least 2MHz, but Mini-Circuits published specifications tend to

Hi I ordered the minicircuits JSPQ-65W+ for a new project. 73, Rolf RX: SIR-2115, G69/31DDC, PERSEUS, SIGNALHOUND, AFEDRI, GRX-LAN…… ANT: T2FD, G5RV, ALA 1530/100, GA3005, X-ONE, DISCONE SW:

Yes Martin. With a 90 deg. Phaseshift the directional pattern of the E-plane of the dipoles then rotates with the period of the Signal by 360 degrees. Thus the average horizontal rms Rotation ist

Hi Fred, Rick did also say to include a 1/4 wave transmission line in one leg, in order to introduce a 90 degree phase shift at that specific frequency. This method is typically used in coaxial

are you sure, Rick? As far as i know: if you combine two orthogonal dipoles ( X-dipole) via an 180° coupler you only achieve a +45° oder a -45° Skew of the E-Plane directional pattern of the

Typical, I found the book title just after I'd pressed send. It's a bit pricey new, so I'd try and borrow a copy, via your local library (remember those). "Lumped Element Quadrature Hybrids" by David

You may also wish to look out for an article entitled "How to design wide band RF quadrature networks" Page 5, QEX, November 1982, published by The American Radio Relay League. Another source is "The

Hi Hisami, All 90 degree hybrids tend to be relatively narrowband devices. However, you can extend this by adding more phase shift sections, with their corner frequencies offset by suitable amounts.

Hi Martin, Thanks for the schematic. I see that in principle, it is narrow bandwidth. With the help of NanoVNA, I think I can adjust it. I will give it a try. By the way, it seems that Mini-Circuits

Hi Fred, Hi Martin, Now I can understand the difference between "90 degree hybrid" and "0 / 180 combiner" Thank you very highly for your help. 73, Hisami 7L4IOU

Hi Matthias, Thank you very much for your valuable information. The schematics and pictures are helpful. Especially, I could understand the mechanical structure very well. I will try to translate. tnx