Questions tagged [yagi]
The common name for a Yagi-Uda array antenna, a directional antenna consisting of a dipole (the driven element), a reflector and zero or more directors. The more directors, the more gain and the narrower the beam.
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Is a boom important to a Yagi?
I am trying to make a yagi for a 900M. The tinkering starts causally with some 1.2mm welding wire (cut to size based on K7MEM yagi calculator, direct soldering, no special matching as suggested on ...
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How to convert device with Monopole antenna to Directional/Dipole antenna?
I'm trying to increase the transmission range of a stationary wireless microphone toward its receiver by connecting a yagi antenna. Aside from the antenna sticking out of the top, I don't know where ...
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feeding a 20 meter 2-element yagi in an attic
I have an unused attic crawlspace in which I can potentially install a 2-element 20 meter yagi. I know that adding the reflector will drop the feedpoint impedance of the driven element below 50 to 70 ...
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Will two nearby yagis on different bands interfere when transmitting at the same time?
I'm working on a digital ham radio project that will require two 2m and/or 70cm yagi antennas to be transmitting and receiving in somewhat close proximity to each other. Each will have it's own ...
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Phase-tuning Yagi-Uda antennas
Related to my earlier question around the TET-Emtron HB35C antenna. It is advertised as a:
The HB35C is a full size tri-bander, efficiently utilising the DUAL
DRIVE HB9CV system with the ...
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Dual driven-element Yagi-Uda antennas
Came across the TET-Emtron HB35C antenna which is a:
"The HB35C is a full size tri-bander, efficiently utilising the DUAL DRIVE HB9CV system with the revolutionary “PHASE TUNED” VK2AOU multi band ...
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How to Feed 2 x Co-Phased 4 Element Yagi Antennas?
I am wanting to build 2 x 4 element vertical yagi antennas for 28 MHz and co-phase them and feed with one 50 ohm coaxial transmission line.
If i were to use a gamma match for each yagi and tune them ...
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VHF Balancing, necessary? Methods?
This is a question about power dissipated due to radiation and ohmic heating caused by common mode current in the coaxial shielding, specifically at VHF frequencies.
When a balanced antenna (such as a ...
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Which way is a yagi polarized?
I am installing a yagi antenna that will receive signals from multiple omni antennas that are vertically polarized. Which way should the elements of the yagi point to match? Up and down, or horizontal?...
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Boom length of a Yagi antenna
Apologies in advance if this question is too straightforward. I was browsing for some information about the dimensions of Yagis. This yagi listed by PEOSAT, called Cue Dee 15144AN, is stated to have a ...
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Do these look like amateur radio antennas?
I am planning to move into a new apartment, and of course would like to install a HF antenna there, on the roof if possible.
Today I noticed a small Yagi antenna on the roof of the building , more ...
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Will a HF beam antenna on rooftop building interfere with other antennas there
I am moving into an apartment on the top floor of a building and I intend to install a HF beam antenna for 20 to 10 meters, on the rooftop of the building.
I notice that there are already some ...
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Mounting a hex beam on top of a high urban building
I am moving into a new apartment in the city soon which is on the 24th and last floor of an apartment building. I will have access to the roof of the building also.
I'm still trying to understand ...
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I'm looking for an effective beam antenna for both 20 meters and 10 meters
My favorite HF bands are 20 meters and 10 meters.
I am currently using a multi-band vertical antenna, but it's not so great for DX'ing. I am looking for a good upgrade.
I'm still learning a lot about ...
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Yagi antenna isolation from other Yagi antennas
I have multiple Yagi antennas horizontally polarized. They are all placed in closed proximity at the same height horizontally and operating in a similar frequency.
The yagis are 2.45GHz, bluetooth ...
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3D Printed yagi antenna
I'm trying to produce a Yagi antenna for the 2.45 GHz band using a 3D dual extruder printer. The idea is to print the antenna elements using a metal filament and encasing it all in plastic.
The ...
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Stacking Two UHF Yagi Antennas
Aloha!
I have two HYS TC-YG05 Yagi antennas that were gifted to me and I would like to stack them side by side ( Collinear), in the vertical orientation for some local weather balloon telemetry data ...
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How do 'plumber's delight' type Yagi antennas have a bandwidth?
For Yagi antennas where the driven element is electrically connected to the boom like the parasitic elements, how can this function without diminished performance outside of the design frequency? In ...
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Half wave dipole with parasitic element, (Gain calculation)
good morning all,
I have difficulties to find the correct formula that allows me to calculate the gain of half wave dipole in parallel with another parasitic half wave dipole.
I'm trying to calculate ...
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Yagi Antenna - Elements Length
I am currently modeling a yagi antenna using Matlab and after I optimized the antenna, it gave me a director length shorter than the exciter itself (even if the optimization gave me a good gain).
From ...
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Yagi performing far worse than a dipole
A few months ago, I built a 6 element yagi: 3 driven elements, and 3 reflectors. For 10-15-20m. I was able to tune it to SWR 1:1 for the FT8 frequencies in each band. This antenna is only 6m above ...
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Built a 2 meter 5 element Yagi
Straight dipoles. I can't get the Yagi to tune. I have tried the 4:1 Balun method with coax but not able to tune. With the straight unbalanced input to the dipole I get a 1:1 swr on about 129 MHz ...
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Pondering variations on the vertical bazooka antenna
I've seen these antennas built out of coax that are called a bazooka vertical. It's a kind of 1/4 wave vertical, or perhaps a 1/2 wave dipole. Constructing such an antenna is to roll back the outer ...
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Outdoor Terrestial Digital TV Receiver Antenna: 500-700 MHz Band, Can I Make It Work Better?
See the unconventional antenna shown below, The whole antenna is made of two mirror-imaged Alum metal stampings on either side of a 2-cm hollow 31-cm long rectangular plastic boom. The antenna top and ...
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Should I not have "painted" my YAGI?
I have a 5 ele YAGI which, once we can go multi-op portable again in the UK, I shall be taking to the hills with me.
The idea being to make it quick and simple to get the dimensions and element ...
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Variable polarization Yagi using two antennas on the same boom, joined together with variable feedpoint phase?
I have been trying for ages to find a way to mount a 10 m vertical Yagi properly, so that the mounting pole doesn't stuff up the impedance and radiation pattern, and have had no luck so far. Apart ...
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Can half of a directional antenna (Yagi-Uda, HB9CV) be replaced by a ground plane?
Consider a center-fed dipole antenna. It‘s well understood how the bottom element can be replaced by a ground plane (in practice, generally a few rods but in principle a conducting plate would work as ...
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Yagi: split or solid driven element?
Short question:
What are the advantages and disadvantages of using gamma (solid element) or beta (split element) matching a yagi?
Long question:
A while ago I built a coil loaded yagi for the 20M ...
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What is the effect of coil Q on a shortened dipole?
I made a small yagi, with the driven element being a coil loaded dipole. What is the effect of coil Q in this situation?
The coils I built are 18 turns of 1.2mm enameled wire wound tightly with a ...
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Gain of Yagi turnstile?
I am currently working on a system to communicate with amateur CubeSats. I have decided to use the turnstile crossed-dipole style yagi because it is relatively easy to construct and uses circular ...
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Can I build a Yagi antenna for my Baofeng UV-5R?
I would like to build a Yagi antenna for my Baofeng UV-5R, but I'm a total newbie when it comes to amateur radios. The antenna will be for UHF and shouldn't be too long (like 1.5 meters max).
So my ...
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Beam antenna changed directivity
My Hy-Gain TH6DXX antenna has been up on a tower about 20 years, with excellent results. Suddenly, the gain of the antenna is off the side; in other words, when the boom is broadside to the ...
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2m 5-element yagi with staggered driven elements
I have seen sketches of 3-element 2m yagi antennas in which the driven dipole elements are staggered i.e., one element is positioned slightly in front of the other along the length of the (plastic) ...
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How can a vertical Yagi for 10 m be mounted on on a vertical metal mast and be made to work properly? [duplicate]
From a reply to a previous post I've been told that a horizontal tube half a wavelength long mounted right at the junction between the boom on a vertically mounted yagi and a vertical metal pole will ...
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What happens to a vertical Yagi when you mount it on a vertical metal pole?
How much difference does a metal pole make when it's sitting in the middle of all the lower elements of my beautiful new highly optimized to the max YO.EXE 10 m yagi ?
I get it that the closeness of ...
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Yagi vs Parabolic Dish for 2.4GHz Campus Wifi from 1,800ft away?
My apt balcony is 1,812 feet exactly from my campus's Wifi access point behind a triple pane, brick, 4th floor building window. There is a clear line of sight. I was interested in seeing if I could ...
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How to use 70 cm WiMo phasing harness for a COTS crossed yagi antenna?
In order to generate circular polarization in a crossed-yagi, a 90° phase delay is required between the horizontal and the vertical antenna. In practice, this is achieved either by making a mechanical ...
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Yagi-Uda antenna - energy flow density calculation
This task is our milestone, even the lecturer doesn't know how to do it, I will be grateful for even the smallest clue, thank you in advance.
There are given two, identical, parallel, short dipoles ...
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Can I use two yagi aerials back-to-back for a bi-directional system?
I need to create a setup where I have three radio transceivers (869.4MHz) setup in a straight line.
I need to be able to communicate, in both directions, from the centre pole to the outside two poles,...
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What is the easiest way to eliminate a beam antenna's backward radiation (rear lobe)?
I tried a metallic reflector which works well in terms of radiation, but considerably degrades the return loss and adds more complexity to the design.
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Intermittent High SWR
Using a Cushcraft MA5B beam, when I apply high power from an amplifier, the SWR will go up and down intermittently. Something is breaking down at high power (200-500 W).
I have a new coax feedline, ...
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Which antenna would you use?
I'm starting to study RF propagation at college, and I'm thinking about what antenna I should choose for this scenario:
The distance between the transmitter and receiver is just 700 meters, and the ...
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How to adapt commercial VHF yagi for 2 meter amateur use?
I recently acquired a Decibel 3-element VHF Yagi that was formerly in commercial service. I connected my MFJ-259B antenna analyzer to the antenna and found its minimum SWR at 155 MHz. I have not ...
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Feeding a dual-band UHF and VHF Yagi antenna
I just built a UHF Yagi antenna for my HT, and I was thinking about adding VHF elements. If I do, could I just connect the coax directly to both sets of elements without a diplexer?
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Can 2 uhf beam yagi antennas be used on a transmitter to get a diversity effect?
I'm having a problem getting a good signal up to a repeater site on UHF. I'm running 20W in a neighborhood with lots of trees, and the signal is fading in and out due to trees and the wind.
I can't ...
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Steel Directors with Copper DE
I found old plans for a quagi that uses copper for the Reflector and Driven Element and any 1/8" metal available for the directors. The general recommendation for antennas is: no steel for the DE. Is ...
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What parameters are currently possible in a directional antenna less than 5mm long?
I'm curious what kind of directional antennas could fit inside a cell phone, which would require it to be 5mm or less in its longest dimension. I know that the length of a directional antenna is often ...
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Receive directionality of a sub-optimal Yagi
How do I build the best antenna for a given VHF frequency given that an optimal design is too large?
I am trying to understand the properties of a directional antenna of sub-optimal design. All the ...
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Would a 2.4ghz yagi antenna work for Ham Radio?
I am building a miniature yagi antenna that is made for 2.4ghz. Would a 2.4ghz yagi antenna work for Ham Radio?
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Conductive boom vs non conductive boom: what's the difference on a Yagi?
I designed a Yagi antenna using 4nec2, assuming that I would use a non conductive boom.
If I use an aluminum boom but I insulate the elements from the boom, can I keep the same design? How does it ...
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