2/2 (4) element 7/10MHz Yagi (3.9m) Force12 Antennas

Force12 Antennas – A super-compact dualband 7/10MHz WARC band Yagi with single feedpoint

The 4-LFAR-40/30, an Excellent super-compact Dual band LFA-R Yagi for the 40m & 30m bands on a tiny 3.8m boom!

The LFA-R is one of the latest designs from the desk of G0KSC. The LFA-R uses no reflector, just a dipole/LFA hybrid driver laid flat on the boom with one close proximity director. The dual band version has the second band drive element placed close enough for ‘open-sleeve’ coupling to occur in order service can be provided on a second band. This antenna does not give wide band performance (and thus is suited to the WARC bands) but does give incredible levels of gain and F/B permetre of boom. Take a look at the specifications below, we think you will agree this is an awesome performer for such a short antenna!

Performance

Gain on 7.1MHz: 7.22dBi (11.66dBi @ 20m up)

F/B on 7.1MHz: 16.94dB

Gain on 10.1MHz: 7.28dBi (11.94dBi @ 20m up)

F/B on 10.1MHz: 13.57dBi

Power Rating: 5kw+

SWR 7MHz: Below 1.9:1 from 7.05MHz to 7.15MHz (can be set any part of the band)

SWR 10MHz: Below 1.5:1 from 10.1MHz to 10.15MHz

Boom Length: 3.890m

Weight: 35Kg / 77LB

Turning Radius: 6.251m / 24ft

Wind Load: 1.1 Square metres

Wind Survival: 1420KPH / 90MPH

Specification

This antenna deploys elements tapering from 2 inch (50.8mm) to 3/8 inch (9.525mm) for 7MHz with elements starting at 1.5 inch (38.1mm) tapering through 3/8 inch (9.525mm) for 10MHz . The antenna has fully insulated elements which will ensure continuous, high performance for many years to come. Boom to mast brackets are included with all antennas which will support 2 inch (50mm) masts. Boom is 3 inch square 10SWG aluminum.

Our antennas are constructed with the best quality materials in order that the best mechanical construction can be achieved, not the cheapest and most profitable! Even a digital caliper is used to measure the elements during production to help ensure the best possible results when installed.

Note: Much development time has gone into our antennas, not just on basic electromagnetic design, we are able to model the effect of insulators, booms and other objects to ensure the make-up of our antennas has least effect on performance and pattern degradation. More information can be found here