Canvey Island, Essex, England Justin@g0ksc.co.uk
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144MHz LFA Yagis

Low Noise LFA Yagis designed by G0KSC free to build for personal use.

G0KSC Twin-Boom Quads
Custom low-noise dish feeds
Custom low-noise dish feeds
G0KSC Custom Dish Feeds

Above installation @ HB9Q

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G0KSC SC0607L 7el 50Mhz Yagi Antenna with a 7.1 Metre Length Boom

This antenna has been redesigned and represents what I beleive to the the 'ideal boom length' for an OWA direct feed 50Ohm Yagi. This can be seen in the model in the super flat SWR, the high levels of F/B ratio along with the excellent gain and pattern.

The model below is designed with 12.7mm / 1/2 inch elements and also a 12mm element version. If you require a version of this antenna with another diameter wire, Email me and I will remodel. It is NOT POSSIBLE to simply resize the elements when using a VERY different diameter wire and get the best performance in my opinion, I remodel the whole antenna each time. Element positions also need to change for the ideal antenna to be achieved again. Please read all the way down this page, there are other versions of this antenna using tapered elements too. As I have more requests, I will remodel in other element diameters and tapers and publish those too.

The 7.1m 7el at K7JA

A 7el 50 Ohm G0KSC OWA at LA5ZK (a 9el G0KSC 70mhz OWA below)

Dimensions in Metres - all tubing 1/2 inch or 13mm diameter, mail for other sizes and tapered elements

Element spacing:

  • Ref =      0
  • Driven =  .783
  • D1 =       .989
  • D2 =       1.952
  • D3 =      3.456
  • D4 =      5.290
  • D5 =      7.100

Element sizes per element half:

  • Ref =       1.4725
  • Driven =   1.4435
  • D1 =        1.3695
  • D2 =        1.3675
  • D3 =        1.340
  • D4 =        1.3215
  • D5 =        1.272

Performance figures @ 50.150Mhz:

  • Froward Gain: 12.11dBi free space
  • Front to Back: 23.23dB
  • 1:1.1 SWR B/W 700Khz

Dimensions in Metres - all tubing 12mm

Element spacing:

  • Ref =      0
  • Driven =  .783
  • D1 =       .989
  • D2 =       1.952
  • D3 =      3.456
  • D4 =      5.290
  • D5 =      7.100

Element sizes per element half:

  • Ref =       1.474
  • Driven =   1.444
  • D1 =        1.371
  • D2 =        1.369
  • D3 =        1.341
  • D4 =        1.322
  • D5 =        1.273

Performance figures @ 50.150Mhz:

  • Froward Gain: 12.09dBi free space
  • Front to Back: 23.54dB
  • 1:1.1 SWR B/W 700Khz

Azimuth Plot

Elevation Plot

This fantastic antenna at 20m up

 

An Excellent SWR to go with the fantastic pattern!

Remeber, mail me if you have different diameter tube requirements and send photos of built antenna!