G0KSC SC0607M 7el 50Mhz OWA Yagi Antenna with a 7.95 Metre Length Boom

An exceptionally efficient beam for 50Mhz with 100% radiating efficiency. 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 of 1.25inch box section or using a 1.25 inch centre section with a 2 metre length each side (inserted into main boom and fixed) in order to give the full boom length.

This antenna has been tuned for gain rather than front to back to only has .5dB less forward gain than it's big brother the SC0607M. However, Front to Back is well down at 20.29dB from 34dB of the SC0607M.

NO Match losses, NO radiating losses ALL your power radiating from the antenna!!

Dimensions in Metres

Element spacing:

Ref = 0
Driven = .830
D1 = 1.246
D2 = 2.556
D3 = 4.472
D4 = 6.415
D5 = 7.95

Element sizes per element half:

Ref = 1.479
Driven = 1.428
D1 = 1.358
D2 = 1.338
D3 = 1.318
D4 = 1.340
D5 = 1.303

Performance figures @ 50.250Mhz:

Froward Gain: 12.48dBi free space
Front to Back: 20.24dB
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 construction information see 'G0KSC insulators' and the UKSMG article from the main menu on the home page.