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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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13 votes
3 answers
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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 ...
GmodCake's user avatar
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11 votes
6 answers
49k views

What is a Gamma match in the context of the driven element of a Yagi antenna?

How (and why) does a Gamma match work, when used on the driven element of a Yagi antenna? As shown here: (source: http://www.iw5edi.com/ham-radio/?2-element-yagi-for-10-meters-band,49) The article ...
Ron J. KD2EQS's user avatar
7 votes
1 answer
725 views

Is bending the tips of the antenna wires going to affect the effective length?

I'm looking at designs for low cost DIY yagi antennas for a fox hunt, and pondering coat hanger wire and PVC piping. I'd like them to be built by the youth who will be doing the fox hunt, but that ...
Adam Davis's user avatar
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6 votes
3 answers
885 views

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 ...
Ben's user avatar
  • 163
5 votes
4 answers
2k views

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 ...
Engineer999's user avatar
5 votes
2 answers
2k views

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 ...
Gabriel Fair's user avatar
5 votes
3 answers
2k views

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?...
T3chie - Bitoku Labs's user avatar
5 votes
2 answers
360 views

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 ...
Engineer999's user avatar
5 votes
2 answers
498 views

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 ...
jstarek's user avatar
  • 222
5 votes
1 answer
2k views

Connect Printed Yagi-Uda Dipole Array with Balun to coaxial cable correctly

I am making the Printed Yagi-Uda Dipole Array with Balun (that is the full name). I used Antenna Magus to calculate dimensions. I am not sure how to properly connect it to coaxial cable. Here is what ...
Triak's user avatar
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5 votes
1 answer
2k views

Why is optimal polarization different for fm as to SSB/CW

On the article "7db for 7 bucks", which is an article about building a simple three element 2M yagi, they stated that vertically polarizing the antenna is better for FM work, and horizontally ...
Skyler 440's user avatar
  • 7,620
5 votes
2 answers
1k views

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 ...
Aurelia Peters's user avatar
5 votes
1 answer
3k views

How to measure gain of an antenna?

I have dual stacked crossed yagi antenna. How can I practically measure the gain of the antenna combination? I know that this can be done in an anechoic chamber. But this is not feasible for me (...
Vaibhav Rekhate's user avatar
4 votes
4 answers
443 views

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 ...
PHOLAN's user avatar
  • 73
4 votes
3 answers
609 views

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 ...
dwitten's user avatar
  • 81
4 votes
2 answers
281 views

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 ...
Engineer999's user avatar
4 votes
1 answer
112 views

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 ...
Mein Tenah's user avatar
4 votes
1 answer
304 views

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 ...
t252's user avatar
  • 697
4 votes
2 answers
2k views

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 ...
RF101's user avatar
  • 41
4 votes
1 answer
102 views

HSMM problems introduced by mismatched antenna feed points

I have been trying to understand the finer points of HSMM, and I ran across this statement about antenna feed points (emphasis mine): 802.11 signals produce very broadband signals, typically 20-22 ...
Mike Pennington's user avatar
3 votes
3 answers
16k views

Spacing between elements on a Yagi antenna

Does anyone know what the spacing between elements on a beam antenna should be? I built a 146 MHz 3 element beam following instructions, and the spacing was 16" between the driven element and the ...
Delta1X's user avatar
  • 71
3 votes
3 answers
5k views

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 ...
Andrew's user avatar
  • 3,693
3 votes
3 answers
1k views

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 ...
Randy Cunningham's user avatar
3 votes
3 answers
573 views

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 ...
User5754448's user avatar
3 votes
2 answers
786 views

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.
bibi's user avatar
  • 31
3 votes
1 answer
421 views

Why would you choose a Turnstile vs Crossed Yagi CP antenna?

Question What is the difference between circularly-polarized crossed-Yagi and turnstile antennas used for satellite contacts? From what I can tell, the crossed elements of a Yagi are electrically ...
KJ7LNW's user avatar
  • 755
3 votes
2 answers
474 views

Fox Hunting w/o yagi to find a lost High altitude balloon payload

First off, very new to ham radio. I wanted to track my High altitude balloon using APRS, and after loosing that payload in a mature cornfield for 2 months, decided to add a micro-fox from Byonics to ...
TomServo's user avatar
3 votes
2 answers
252 views

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 ...
elplatt's user avatar
  • 160
3 votes
1 answer
248 views

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 ...
PHOLAN's user avatar
  • 73
3 votes
3 answers
6k views

How do I construct the driven element of a yagi?

I've been poking around the internet on how to make a Yagi for my HT. I understand all the math for cutting directors and reflectors to length and placing them at the correct spacing for 146.52 mHz. ...
user6099's user avatar
3 votes
1 answer
2k views

Dual-band yagi on single beam: element positioning

I'm planning to build the WA5JVB Cheap LEO Yagi, which is basically a 2M and a 70cm yagi on the same beam for handheld or tripod use. I'm thinking to do a 3-element 2M and a 5-element 70cm design, ...
David KF4MDV's user avatar
2 votes
3 answers
1k views

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,...
Dave's user avatar
  • 123
2 votes
4 answers
2k views

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 ...
Engineer999's user avatar
2 votes
3 answers
790 views

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 ...
Above the clouds's user avatar
2 votes
2 answers
494 views

Can I use different materials when building an antenna?

I'm thinking about building a 3-element beam using EMT for some parts and then steel tubing at each end to get the length of element I need. EMT will give the antenna more back bone but still give me ...
Zane Lile's user avatar
2 votes
3 answers
180 views

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 ...
user avatar
2 votes
3 answers
332 views

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 ...
Francis Archibald's user avatar
2 votes
2 answers
2k views

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 ...
hjf's user avatar
  • 1,209
2 votes
1 answer
244 views

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 ...
Caphlp22's user avatar
2 votes
3 answers
1k views

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?
Enan Srivastava's user avatar
2 votes
1 answer
201 views

Impedance of Yagi boom model in NEC

When modelling a Yagi in NEC the radiation pattern is essentially identical whether a conductive boom is included or not, see pictures below. An explanation says this is a limitation of the method of ...
butterflypea's user avatar
2 votes
1 answer
208 views

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 ...
forestDM's user avatar
2 votes
1 answer
282 views

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 ...
JimPanse's user avatar
2 votes
3 answers
4k views

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?
MrSchmuck's user avatar
2 votes
1 answer
549 views

Should I ground a 2 array crossed yagi-uda antenna?

I am using 2 array crossed yagi-uda antenna operating at 437.025 MHz. Where and how should I ground it? Should I ground at mast of antenna or to its metallic boom?
shweta's user avatar
  • 61
2 votes
2 answers
446 views

Measurement Confusion

I am building a simple antenna from this article 7db for 7 bucks. I am confused on the measurements for the antenna: It looks like there are two pieces of 18 inch PVC pipes connected to a T fitting. ...
Skyler 440's user avatar
  • 7,620
2 votes
1 answer
146 views

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 ...
niels nielsen's user avatar
2 votes
1 answer
200 views

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 ...
Tarik L's user avatar
  • 45
2 votes
3 answers
5k views

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 ...
petrv7's user avatar
  • 21
2 votes
1 answer
997 views

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 ...
Ibtissam Latachi's user avatar