G0KSC SC0605M 5el 50Mhz Yagi Antenna with a 4.4 Metre Length Boom

This is my mid performance 5el Yagi for 50Mhz. It has a moderate length boom and which can be built with two boom thickness, 1inch square or 1,1/4 inch square. Should the earlier be the preference, support long the boom will be required in order to ensure no sag. I will not cover any construction of such in this passage, the building will need to use their own initiative in order to achieve these support goals.

The SC0605M at KF6A

'The SWR curve is where I want it to be with NO tweaking of the driven element....'

' BTW, it rained hard for 3 hours straight today and my SWR didn't flinch...'
- 'KF6A

Dimensions in Metres

Element spacing:

• Ref =      0
• Driven =  .729
• D1 =      1.223
• D2 =      2.791
• D3 =      4.405

Element sizes per element half:

• Ref =       1.476
• Driven =   1.446
• D1 =        1.373
• D2 =        1.345
• D3 =        1.313

Element diameter:

Each element is made out of single piece 1/2 inch (12.7mm) aluminium tubing Each element half length needs to be doubled in order to gain your total element size. No difference is length needs to be calculated for the 1inch or 1,1/4 inch boom as the elements sit high enough above the boom for the boom to have no influence.

NOTE:

You can build this antenna with 13mm diameter tubing using the same parameters above. Slightly higher front to back ratio and forward gain will be seen along with a narrower SWR curve.

Construction

For construction information, see 'G0KSC Insulators' and 'UKSMG Article' on the fornt page, 'Main Menu'. The builder should be able to obtain most information required there and if there are any additional questions, please mail me:

justin '@' g0ksc.co.uk