Hamradio Homebrew 2 Meter Square Dipole Plan

Here is a plan for homebrewing a 2 Meter Square Dipole plan. The advantage of this antenna is that it is unidirectional, and it takes less space than the regular 2 meter dipole. The calculation included on the diagram below is for building the antenna using copper tubing, you should use MMANA-GAL or other antenna simulation software to come up with new dimension for other materials (aluminium, wire, etc).

2 meter square dipole plan

2 meter square dipole plan

Click on the diagram to enlarge it. Hopefully this will help you in brewing new antennas! Original plan taken from KOFF website

The Homebrew Slim Jim Antenna Gain

I’ve been searching for information regarding the radiation angle and the gain of slim jim antenna, but found none of it. So I decided to build the model of the antenna inside the ever useful MMANA-GAL software to get the information I needed myself.

From what I can surmise, the slim jim has a slightly lower radiation angle than vertical dipole antenna and is easier to mount, thus it is suitable to use for point-to-point communication VHF-UHF operation. It has a gain of about 2.8dBi-3.2dBi in free space and 4.8-5.8dBi when mounted at about 30feet from the ground. Here’s the result of MMANA-GAL :

Slim Jim 9w2wtf

Slim Jim mounted 30 feet above ground
Slim Jim Antenna gain

Slim Jim in free space

Moxon Antenna Plan for 27MHz CB and Freeband Operation

Here’s another 11 meter Moxon Antenna plan suitable for 27MHz CB, Freeband and lower 28MHz Amateur Radio operation band.

10 meter moxon
27MHz CB Moxon Antenna

Dimensions
A- 392.09 cm (154 3/8 inch)
B- 58.62 cm (23 1/16 inch)
C- 11.25 cm (4 7/16 inch)
D- 73.4 cm (28 7/8 inch)
E- 143.27 cm (56 7/16)

Gain, Radiation Pattern (mounted at approx 30feet)

Gain : Approx 10-11dBi (30 feet above the ground)
Freq range : 27.300 MHz – 28.300 MHz

11 meter 27MHz CB Homebrew Moxon Antenna

The main advantage of Moxon rectangle antenna are :

  • Compact and Small
  • Has considerable gain
  • It can eliminate noise on HF band
  • Easy to construct
  • Suitable for HF operation (mid-low radiation angle)

Refer here for 10 meter Moxon Antenna Plan for Amateur Radio operation (28.2MHz-28.8MHz) : 10 Meter Band Compact directional antenna, Moxon

2 meter 5/8 ASTRA Antenna Plan – KakiBiawak

I think many of you might have heard about this particular 2 meter VHF antenna. Called
“Antenna ASTRA” which derived from the name of one of the most popular Amateur Radio Society in Malaysia.

Here is the details of its construction. Click on the photograph to enlarge it.

Plan Homebrew Antenna ASTRA 2 Meter VHF

KakiBiawak @ Astra Antenna in action

Antenna Astra

Homebrewing 6 Element OWA VHF Yagi (10dBi) – hamradio

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

Continue reading “Homebrewing 6 Element OWA VHF Yagi (10dBi) – hamradio”

Youtube: Morse Code Practice Oscillator in Action

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For starters… It does not actually sounds like that, I had to lower the voltage because the speaker output is too loud and you can hear that i’m not a good at sending morse too.

Still in progress, I’m still looking to modify it abit and put it in a nice box and attach it with a decent key.

At last my Morse Practice Circuit Completed – sort of

As promised in the previous post,Simple Morse Practice Oscillator Circuit has been completed. Sorry, I cant do anything much with the photo quality as it was taken using my stupid mobile phone.

Morse Code Oscillator

I promise to include a Youtube video demonstrating its sound and operation. Next, I need to get a decent casing and some cheap morse keyer to go with this oscillator. I might be planning to make one that could interface with CWirc too.