• G0KSC designed 3el, 40M & 6el 20M (Force 12)

    This antenna uses the G0KSC OP-DES design on both 40m and 20m to provide full-band coverage on each.

  • 6 x 7el WOS 50MHz LFA Yagi

    175' fully rotating tower and 6 x 7el 50MHz WOS LFA Yagis at W7EW

  • 3 el 24MHz LFA Yagi by InnovAntennas

    Serious low-noise performance for the HF bands too!

  • 4 x 6el 50MHz LFA Yagis @ DL5WP

    Those that do their research and want low noise Yagis choose G0KSC designs!

  • 4 x 11el 144MHz LFA's @ F3EGA

    Excellent G/T figure antenna array ensuring F3EGA can hear and be heard!

  • G0KSC Monoband 14MHz Log Periodic

    With a boom of just 2m and F/B in excess of 20dB including full-band coverage, this is a super-compact Field day antenna!

  • 4 x 24el 432MHz LFA @ PA2V

    PA2V selected G0KSC LFAs (built by InnovAntennas) when he wanted the very best in EME performance!

  • 4el 27MHz LFA Yagi by InnovAntennas

    A 4 element 27MHz LFA by InnovAntennas. The LFA can handle 20KW plus and does for many radio stations, commerical and hobby!

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Those that have entered into a discussion with me on this subject would not be surprised to hear my recommendations; Give up gain !!

Many of us live in city locations and have noise from many directions. It does not matter how much gain you have, if the noise is there it is there, masking wanted signals and preventing best possible performance. I most cases, giving up .1dB gain equals a 1dB reduction in the antenna rear 'bubble' and hence a much greater reduction in unwanted noise is seen than the drop in forward gain. Sure, the station you received at -28 (your limit) may now drop to -29 it you took my advice to extremes. The difference is, you can now hear stations at -30 and -31 too. It has always been the case that you can work what you hear but how many times are you told you were being called and don't see a thing?

 

While the antenna design is one thing, my opinion extends to encourage 'understacking' of any multi-antenna array within noisy locations to further reduce noise and unwanted signal pick-up. Unless you are living on a farm in the middle of Texas, it is likely you are effected by 'city noise'. If this is the case, any Sky temperature and G/T assements go out of the window, drastic measures need to be taken in order that you can hear those weak signals.

 

The LFA and OWL produce very high levels of gain so don't be misled. However, they are designed to provide the highest levels of gain achievable while maintaining antenna bandwidth and a tight, clean, low noise pattern too in order that the ultimate experience can be achieved.

This Urban noise issue is not limited to 2m. Some antenna designers will tell you noise does not play a role in receiving signals on 2m, 4m and even 6m, this is naive. Sky temperature is one thing, man-made noise and it's affect on received signals in the real-world completely another. Follow This (bad) advice and you will see the same receive restrictions that have limited antenna performance for 20 years or more. Want to be a leader rather than a follower? Then read on !

 

 

The VE7XDT 4 x 8el 2m LFA

Take Dino, VE7XDT as an example. He built 4 x 8el LFAs for 2m EME after advice from Lionel, VE7BQH. He also took my advice and installed my 'Antenna Balun' which provides bandpass filter characteristics and a DC ground to the loop (to further decrease noise). The results? Not just can he now hear what others can't, he is seeing some exceptional signal strengths too due to a much lower noise floor. Take a look at his comments below:

 

'Here it goes:

Installation was on Saturday , August 14.
Started EME on Sunday , August 15.
Saw very strong signals from CT1HZE but no contact.. Then decoded very strong signals from VK2KU at -23
He could not hear me with my 120W at antenna...
Then worked Mike K6MYC .. my first contact.. he gave me -23

Here is the fact: I was the only NA station that copied VK2KU at the time.. Dgrg was -5.0 db...

Here is another fact: compared to 2xM2 12 el that my friend has in Vancouver - he could not hear nor see what I was seeing...
I took pictures from the screen to prove it to him..

Here is another fact : W5UN came on , Dgrd was -7.0 db , I copied him -23 db... he did not copy me ...


I am very happy with the performance Justin, just not enough power from this end..'

Dino VE7XDT

 

This is an earlier mail from Dino when testing the array for the first time

 

'Your antennae are PERFECT!!!

We calibrated my MFK 269 first. After that we tuned the 4 antennae - all came

with in 1/2mm accuracy in dimensions!!! There is 250KHz zone with SWR

being 1.0:1 - amazing!!! Lionel (VE7BQH) was impressed .

Today I will try to bring the existing antenna down and install the EME array.
I would like to participate on the contest during the weekend.

Once again these antennae tune like a charm!!!'

 

How can it be this good? G0KSC only uses the very latest commercial antenna design technology, not out-of-date, innacurate freeware modelling packages that have their issues. This is one reason why if you view an LFA in any antenna design package not using NEC4 (or FEKO and HFSS by Ansoft which are OK too) you will not see the correct impedance and SWR).

 

VE7XDT receiving VK2KU at an incredible -23 best. A completed QSO if VK2KU used LFAs??

As can be seen from the above screenshot, it was not a fluke copy or a renowed JT6M guess, this was a decode each and every over when no other North American station was hearing VK2KU. What is even more impressive is receving VK2KU at -23 when the moon angle was providing a signal degredation of  -4.2dB on top of this! This confirms again what many hams have been realising; the LFA is the EME tool of tomorrow. Superior receive performance when compared to traditional Yagi antennas.
 
IV3MUR is hearing 'above his station' with a single 8el LFA at just 2' above ground!
 
IV3MUR proved earlier this year the LFA was a serious EME contender when he set up his 8el LFA on a small post in the garden. Excellent signals where seen with such a small antenna. Take a look at the example below:
 
IV3MUR completing with EA6VQ in straight overs with 100w and an 8el LFA


This straight overs QSO with EA6VQ above saw EA6VQ being received at an incredible -17dB. Remeber, this is a single 8el LFA parked next to the ground!
 
If you want the best EME performance there, is just one choice; The G0KSC LFA !!
 
73
Justin G0KSC


 

 



 
 
 
 

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