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Re: HYBRID QUADRATURE JH-6-4 or equivalent
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 one spot frequency, this could work.?
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However, the 90 degrees shift is only likely to be present over a relatively narrow bandwidth, and the change in phase either side would probably be fairly rapid.
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Regards,
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Martin
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On Tue, Apr 22, 2025 at 09:46 PM, hisami dejima wrote:
If the coil is 10uH and the capacitance between the windings is 4pF (2x2pF), it seems to behave as it should at about 25MHz. |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
Hi Martin and All
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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 LTSPICE. ?
If the coil is 10uH and the capacitance between the windings is 4pF (2x2pF), it seems to behave as it should at about 25MHz.
I added a 100pF capacitor and it seems to work as a splitter/combiner at 3.5MHz.
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It is a crude simulation, but if the 3dB loss is acceptable, it could be used as a mono-band 90 degree Hybrid.
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I put the two pictures and the LTSPICE source in text on my brog.
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tnx & 73, Hisami 7L4IOU
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
I will be interested to see how well that performs outside its specified frequency range.
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I suspect it would actually work OK down to at least 2MHz, but Mini-Circuits published specifications tend to be cautious.
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Regards,
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Martin
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On Tue, Apr 22, 2025 at 03:14 PM, Rolf Haenggi wrote:
I ?ordered the minicircuits JSPQ-65W+ for a new project. |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
开云体育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:? ?go2signals Software Suite Logs: ? From: [email protected] <[email protected]> On Behalf Of hisami dejima via groups.io
Sent: Monday, April 21, 2025 11:04 AM To: [email protected] Subject: [loopantennas] HYBRID QUADRATURE JH-6-4 or equivalent ? Hi All, ? I came across "The R&S HE-015 active antenna" by chance. ? In the pictures there, the combiner seems to be "anzac JH-6-4". ? I have some home brewed Small Loop, Active Dipole and Mini Whips,? ? The key component JH-6-4 is also listed on DigiKey, but price is exorbitant! ? the datasheet here ? Does anyone know what the JH-6-4 or equivalent is made of or how it works? ? I imagine it is probably a device like this. ? What do you think? ? tnx & 73, Hisami 7L4IOU |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
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 quasi omnidirectional. Orthogonal to the E-plane the polarisation ist circular.
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reference: Kraus/Marhefka "Antennas and wave propagation 4th ed" Chapter 15-7.
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regards, Fred |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
Hi Fred,
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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.
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This method is typically used in coaxial phasing harness, for VHF & UHF frequencies.
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Regards,
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Martin
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On Tue, Apr 22, 2025 at 10:55 AM, Fred M wrote:
are you sure, Rick? |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
On Mon, Apr 21, 2025 at 06:37 PM, Richard \(Rick\) Karlquist \(N6RK\) wrote:
1.? If you work at a narrow band of frequencies, you can simply use a 0 or 180 degree hybrid combiner to feed the two loops are you sure, Rick?
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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 dipoles. But not an horizontally polarised omnidirectional pattern.
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regards, Fred |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
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).
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"Lumped Element Quadrature Hybrids" by David Andrews
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Regards,
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Martin
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On Tue, Apr 22, 2025 at 09:15 AM, Martin - Southwest UK wrote:
There is also an excellent book devoted to the subject, |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
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.
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Another source is "The theory and design of lumped element quadrature hybrids"? which can be downloaded at
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There is also an excellent book devoted to the subject, which I think was written by the same person, and based on his Phd, but I can't find the details at the moment.
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Regards,
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Martin |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
Hi Hisami,
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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. The more sections that are cascaded, the more difficult it becomes to align, and the losses also start to mount up.
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I also have an Anzac JH-10-4 20-140MHz 90 degree hybrid, which is a lot more complicated, and incorporates 6 transformers, plus other inductors and capacitors.
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The CSA hybrid I posted is adequate for use across the majority of the short wave spectrum, but it is not good enough for professional beam-forming in military / radar / astronomy, or lab grade use.
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The Mini-Circuits hybrid is most likely intended for use in the IF path of a superheterodyne receiver / transmitter, where it will be operating at a fixed centre frequency. The circuit in the data sheet is just an electrical representation, to indicate which ports are DC coupled, and what impedance is present. I don't think it is the actual circuit, unless the transformer coupling, or some other element, has somehow been "manipulated" to generate the required phase shift, which I think is highly unlikely.
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Regards,
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Martin
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On Tue, Apr 22, 2025 at 12:24 AM, hisami dejima wrote:
Thanks for the schematic. |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
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 are readily available for commercial 90 degree hybrids.
I searched a few,?
SCPQ-10.5+ was the cheapest. ?
and I was surprised to see the datasheet.
The electrical schematic at the bottom right of the DATASHEET is quite simple.
Is it actually one bifiler transformer and one resistor? Or is it just an illustration? ?
from View data
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AMP UNBAL (dB) <1?
9MHz 0.95 - 11.3MHz 0.95 appears to be the origin of the specs. If do not want to be exact,? 7MHz to 14MHz looks like a practical range. ?
In any case, it looks very simple and I will try later.
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tnx & 73, Hisami 7L4IOU
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
开云体育
Digikey much better price than Mouser $9,694.21? :) No, the link to a homebrew coupler is for versions with either a 0 or 180 degree shiftJohn??? KK6IL On 4/21/2025 2:03 AM, hisami dejima via
groups.io wrote:
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
I have posted a couple of pictures.
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Note that the part numbers in the simplified circuit diagram are not the same as those marked on the original PCB. I had only used the minimum amount of detail to be able to run a simulation using Qucs Studio.
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It should be useable from approx 2MHz to almost 30MHz.
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The shifts are not exact 90 degrees over the entire frequency range, but they are close enough for the intended purpose.
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Regards,
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Martin
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On Mon, Apr 21, 2025 at 03:29 PM, Everett N4CY wrote:
Please send me what you have in the way of circuits? |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
开云体育1.? If you work at a narrow band of frequencies, you can simply use a 0 or 180 degree hybrid combiner to feed the two loops, except you make one feedline a quarter wave longer than the other.? Commonly used at VHF. 2.? You can also make a narrow band 90 degree hybrid combiner using a single 1:1 transformer and 2 capacitors and 2 inductors.? I designed one of these into the 5071A atomic clock.? Now still in production after 30+ years. 3.? If you need a broadband 90 degree combiner, you need one transformer with a center tap and a second impedance match transformer.? If you want for example a 100:1 bandwidth, then you need something like 16 inductors and 16 capacitors.? I have actually built several of these, which worked. ---
Rick Karlquist
N6RK On 2025-04-21 08:29, Everett N4CY via groups.io wrote:
Hi Martin, |
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Re: Pixel RF30C preamp
For general info, this preamp was designed by Jack Smith K8ZOA (now SK); I built the first 25 of them for him. The preamp is a nominal +30 dB 50 ohm in/out preamp with a balanced Norton input followed by a balanced bipolar output. (I have contacted Joe privately about a schematic.)
73,
Steve AA7U |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
Martin,
with two horizontally polarized turnstile dipoles you get horizontal linear Polarisation and an omnidirectuonal pattern.
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You get circular polarisation only in the vertical direction, orthogonal to the linear polarized plane of thevdipoles.
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regards, Fred |
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Re: HYBRID QUADRATURE JH-6-4 or equivalent
Hi Martin,
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Please send me what you have in the way of circuits? Everett On Monday, April 21, 2025, 9:53 AM, Martin - Southwest UK via groups.io <martin_ehrenfried@...> wrote:
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Everett N4CY
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