G0KSC SC0608M 8el 50Mhz OWA Yagi Antenna with a 9.95 Metre Length BoomThis 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 of 2 metres to help support the boom. This antenna will require guying to the support post from each end. I recommend, 3 metres along from the centre in each direction. 
MM0GPZ built the 8 element 6M G0KSC OWA Yagi form the RSGB 2009 Field Day Dimensions in Metres
Element spacing: - Ref = 0
- Driven = .976
- D1 = 1.273
- D2 = 2.402
- D3 = 4.083
- D4 = 6.008
- D5 = 8.291
- D6 = 9.95
Element sizes per element half: - Ref = 1.478
- Driven = 1.467
- D1 = 1.383
- D2 = 1.358
- D3 = 1.335
- D4 = 1.318
- D5 = 1.308
- D6 = 1.277
Performance figures @ 50.250Mhz: - Froward Gain: 13.25dBi free space
- Front to Back: 29.17dB
- 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. 
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8el 9.95mtr Boom
