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

Ham Radio, Photos and Travels May 1st, 2008

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

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How to measure SWR using Diamond SX SWR meter

Ham Radio March 22nd, 2008

Here’s a simple tutorial on how to measure Standing Wave Radio (SWR) for your stations setup using Diamond SX series (SX-200,SX-400,SX-600) SWR meter, commonly available in Malaysia and Singapore.

This guide assume that you are measuring SWR for a VHF antenna operating on 2 meter amateur radio band (144 MHz – 148 MHz), voice FM.

Step 1
Firstly ensure that you’ve connected your rig and antenna to SWR meter securely. Ensure that the “blue button” is not depressed.

SWR meter Diamond SX-200

Step 2
Find a frequency that is not in use. Ask first to ensure that nobody is using that frequency, never ever perform SWR testing on Repeater input or output frequency.

In northern part of Malaysia, 145.575MHz has been set aside as a testing frequency.
Icom-v8000 mypapit radio

Step 3

Ensure that you set the SWR meter switch setting to CAL as in the photograph.

Make sure your rig is set to transmit on the lowest power level setting acceptable by the SWR meter (usually around 5watt), any interference should be minimized.

Press PTT button and id your station, example “9W2QRT testing…”, make sure you use your own callsign!

PTT ICOM V-8000 mypapit radio

without releasing PTT, adjust the CAL knob on the SWR meter until the needle points to red arrow to “CAL”, refer to photographs below.

hamradio SWR meter testing

SWR meter calibration

Step 4

Finally, without releasing PTT, turn the switch on the SWR meter to “SWR”, as shown in photograph :

how to measure SWR in amateur radio

The meter will display SWR for your antenna setup. In this case 1.5:1. Dont forget to release PTT button after the test. To ensure your antenna is useful accross the band, you can repeat the test on amateur band edge, that is on 144.000 MHz and 148.000MHz.

Final thought
Remember, all test should be brief, and accompanied by your callsign, never ever transmit on repeater inputs or on busy channel.

That’s all folks.

p/s: Please leave comments if you have any information or wish to correct mistakes in this tutorial.

The Bahasa Melayu version of this guide is available on Forum Ham Radio Anak Perlis

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