G0KSC SC0610M 10el 50Mhz OWA Yagi Antenna with a 14.9 Metre Length Boom

This is a nice DX beam for 50 Mhz. As always it has a nice flat SWR curve and is built with in a non-critical format so any small errors you make whilst constructing will not have a huge impact on performance.

I recommend this to be built from 2 X 5 metre lengths of 1.75inch box section aluminum tubes with a 2 inch box section in the centre. This antenna will require guying to the support post from each end. I recommend, 5 metres along from the centre in each direction.

This is a very efficient model. For every 1 Watt that enters this antenna, 1 Watt is radiated. NO structure losses, NO matching losses. Check other models for this efficiency!

Dimensions in Metres

Element spacing:

• Ref =       0
• Driven =  .74
• D1 =       1.051
• D2 =       2.37
• D3 =       4.134
• D4 =       6.26
• D5 =       8.48
• D6 =      10.81
• D7 =      12.983
• D8 =      14.9

Element sizes per element half:

• Ref =       1.489
• Driven =   1.477
• D1 =        1.39
• D2 =        1.361
• D3 =        1.336
• D4 =        1.315
• D5 =        1.306
• D6 =        1.296
• D7 =        1.301
• D8 =        1.248

Performance figures @ 50.250Mhz:

• Froward Gain: 14.7dBi free space
• Front to Back: 28.02dB
• Radiation angle at 10 Metres above ground: 10 degrees

Element diameter:

Each element is made out of single piece 1/2 inch (12.7mm) aluminum tubing Each element half length needs to be doubled in order to gain your total element size.

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. For other element diameters, please Email me.

For construction information see 'G0KSC insulators' and the UKSMG article from the main menu on the home page.