I took some time off to build my first HF antenna using the plan I’ve obtained few months ago. I chose moxon as my first 10 meter HF antenna as it is small and compact and it is directional, allowing me to focus it into a single direction for a pretty quiet QSO, without much interference.

The material I used in building this moxon are :

  • Green ground (12 Gauge ?) wire, it has 7 copper wire inside it.
  • PVC pipe (3/4″ diameter) as necessary to hold the wire in place, you can use other materials too, as long as it formed the basic dimension of moxon antenna

Antenna Plan and Results
I use the plan described in this post; 10 Meter Band Compact Directonal Antenna and started building it immediately. The result of the antenna can be seen here :

9w2wtf moxon

9w2wtf moxon

Performance
Although I build it only as a temporary antenna (thus its flimsy), it performed rather well when compared to other types of popular 10 meter band antenna in my place (Delta Loop, Inverted-V) as the antenna is directional and it does not requires the use of transformer balun.

I’ve managed to make contact with 12 stations in 6 days since it has been erected.

Some tips working on 10 meter band

  • Use a good low loss cable such as RG-8 or Belden 9913
  • Make sure you know where you point your antenna, the direction of your antenna is crucial if you ever to make contact with distant station.
  • The propagation is pretty good during daytime between 3pm – 8pm by my observation, use that time window wisely.
  • Use directional antenna like Moxon or Yagi as they allow you to focus your transmission to a certain direction and eliminate excessive interference on the band.
  • Be patient

That’s it and good luck!

p/s:
I wouldn’t recommend PVC pipes if you are planning to erect a permanent antenna as they are flimsy. Use aluminium pipes or copper tubes as they are more durable and offers best performance.

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Here are few photos that 9W2AZV and I have taken during the course of building our 6 element OWA yagi with 10dbi gain.

Materials used to contruct the antenna

  • 8mm aluminium tube, 20 feet
  • 6 feet length of 3/4″ PVC plumbing pipe
  • Ordinary household plug box

We use a plan taken from LB Cebik (W4RNL) website, first covered in : 10dBi – 6 element OWA Yagi-Uda Antenna for 2 meter band

Here are the photos of the antenna in construction :

Homebrew 6 Element Yagi 9w2azv 9w2wtf

Homebrew 6 Element Yagi 9w2azv 9w2wtf

Homebrew 6 Element Yagi 9w2azv 9w2wtf

Read the rest of this entry »

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Here are the photos of my homebrew 2 meter VHF antennas. One is 6 element OWA yagi and another is a 2 meter Slim Jim for omnidirectional operation

OWA Yagi 6 element

Slim Jim antenna

OWA Yagi 6 element

The homebrew slim jim antenna was previously featured on my blog as well as its plan. The OWA Yagi 6 element antenna plan can be obtained from this post : 6 Element OWA Yagi Antenna for 2 Meter band plan

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10 meter moxon

Due to the enourmous size of 3 element Yagi and the current working condition on 10/11 meter band, I decided to accept the advice of 9W2RZL and thinking of constructing a directional antenna right after I obtain the 11/10 meter rig (which is maybe around April).

Moxon antenna might suit my need as it is :

  • directional
  • has gain of around 5 dBi
  • Compact and Light weight
  • Easy to construct
  • designed for 50 Ohm impedance
  • Wideband
  • Great F/B ratio, useful for blanking noise

Here is the plan for the 10 meter Moxon antenna, centered on 28.5 MHz frequency.

Dimensions

  • A – 382.43 cm (150 1/2 inch)
  • B – 57.13 cm (22 1/2 inch)
  • C – 11.02 cm (4 3/8 inch)
  • D – 71.06 cm (28 1/4 inch)
  • E – 139.76 cm (55 inch)

These calculation are made for 12 gauge wire using L. B. Cebik Moxon Calculator tool. The Moxon on the above photo belong to Mark Rabel

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Here is a 6 element yagi my friend and I have built for experimenting with directional antenna. Theoritically the antenna has about 10dBi gain in its main lobe and a good Front-to-Back ratio, a perfect substitute if you don’t have means to get the popular V24 Silverthunder antenna.

6 Element OWA Yagi for 2 Meter Band

Radiation Pattern Lobes
OWA 6 element 2 meter band

Dimensions (in inches)
Element, Length, Space from Reflector

Reflector – 40.52, —-
Driver – 39.96, 10.13
Director 1 – 37.38, 14.32
Director 2 – 36.31 25.93
Director 3 – 36.31, 37.28
Director 4 – 34.96 , 54.22

Calculated Center of gravity 23.87 inches

Dimensions (in cm)
Element, Length, Space from Reflector

Reflector – 102.92, —-
Driver – 101.50, 25.73
Director 1 – 94.95, 36.37
Director 2 – 92.23, 65.86
Director 3 – 92.23, 94.69
Director 4 – 88.80 , 137.72

Calculated Center of gravity :60.66 cm

The plan for the antenna has been taken from LB Cebik website. More article will follow that covers our construction of this Yagi antenna along with our reports of its improvement.

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I would like to share with you a compact 4 Element Yagi-Uda antenna design for 2 meter amateur radio band. This antenna has great front-to-back ratio and is optimized for wide range of frequency, a bargain for its compact design (about 76 centimeter long).

Although this antenna has almost the same gain as any simple 3 element yagi antenna (7-8dBi), this design has a significantly improved Front-to-Back ratio which is great for blanking noises and foxhunting purposes

Here how the antenna would look like
Optimized 4 Element Yagi 2 Meter

Front-Back Ratio Gain
Optimized 4 Element Yagi 2 Meter

VSWR from 143.000 MHz to 148.000 MHz
VSWR for Optimized 4 Element Yagi 2 Meter

Antenna dimensions
Element, Length, Space from Reflector (all in cm unit)

  • Reflector – 103.0, 0.00
  • Driver – 95.0, 26.0
  • Director 1 – 92.0, 39.0
  • Director 2 – 83.0, 76.0

Calculated Center of Gravity – 35.0 cm

This antenna has been modelled using YagiMAX 3.0 software by K4VX

Please leave comments if you have sucessfully built this antenna. I would like to hear your experiences.

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Today I want to share with you a great Yagi Uda Antenna modeling software for amateur radio operator and enthusiast.

The most interesting part of the software is, it can help you to improve your design by projecting the antenna radiation pattern and estimating the radiation resistance (impudence) at any given frequency.

The application is created for the venerable DOS environment, thus some of the operating system might not be able to run it natively. However I found out that I can run the application successfully using DOSBox DOS emulator software under Ubuntu Linux. For your information, DOSBox is also available for Windows operating system too.

YagiMAX Screenshots

Here’s a couple of YagiMAX screenshot taken from my computer (running Linux, Ubuntu Gutsy). The antenna shown here is a 6 Element OWA Yagi for 2 Meter amateur radio band, scaled from its 6 meter counterpart, the design was taken from L.B Cebik website

yagimax yagi software model

yagimax yagi software model

Download YagiMAX

Here is a download link to YagiMAX 3.11. Hope that will help you in your work !

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