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

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

144MHz LFA Yagis
70cms LFA Yagis
70cms LFA Yagis
Twin-Boom G0KSC Quads
G0KSC Twin-Boom Quads
Twin-Boom G0KSC Quads
G0KSC Custom Dish feeds - Above installation @ HB9Q
Custom low-noise dish feeds
Custom low-noise dish feeds
G0KSC Custom Dish Feeds

Above installation @ HB9Q

G0KSC Custom Dish feeds - Above installation @ HB9Q
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Read Time: 1 - 2 minutes

The Worlds first 70cms LFA Yagi built and tested - Featured in DUBUS 4

The G0KSC SC19-70FJG  19 element Yagi for 70cms is now built and tested and what an antenna it is. 

Many of my desgins now are bespoke designs at the request of amateurs and this one is no exception. G8FJG (who already uses a 9 element LFA for 144MHz) asked for a 70cms version to complete his UHF/VHF array and I decided to model this 19 element version (at 4.5 metres long) and name it after his callsign, in a similar way to the M2 naming system.

On the bench - The 19SC70FJG ready for testing on the tower

This antenna will be featureds first in DUBUS issue 4 2009 and details of construction of this and other 70cms variants will appear on this site early next year. As with all LFAs this antenna has an exceptional performer and has an ultra clean pattern. The Elevation plot below shows the EZNEC Pro/4 predicted plot with the antenna placed 11 metres above ground upon my tower, with the tower wound down.

Canon shot - the 19SC70FJG has a single super-clean lobe and excellent F/B Ratio

Needless to say, SWR on this antenna is as with all LFAs, flat across its intended bandwidth being 432 to 433MHz and the antenna is ultra low-noise too. The analyser shot below shows the actual SWR and plot with the antenna installed on the test mast. Excellent stack results occur at just 80 cms apart so multi-LFA 70cms arrays will not be out of reach of most hams wanting to experiment with this band.

Subscribe to DUBUS if you want this and other interesting designs first. The new LFA 'Plus2' Yagi is also featured first in DUBUS issue4 with details of a DUBUS exclusive 15 element design too.

SWR King - the SC19-70FJG  showing 1.03:1 at 432.400 and the plot (opporsite the SWR) shows a flat line

G8FJGs 19SC70FJG built and installed on his tower ready for testing

Become one of todays hams making the step towards a new era in Yagi technology, get yourself an LFA today!

Justin G0KSC