Happy New Year to all club members
I thought I would post an update on the proposed antenna for MSARS at Cyprus Hall.
As previously mentioned, this will be based on a half wave ended design using a 64:1 matching transformer at the feed point.
I have this in place at home now for testing and have been trying it with the mast wound up and the antenna at 39 feet plus also with the mast wound down and the antenna at 22 feet.
The reason for this is I thought it would be useful for others to know how it would perform if someone chose to use it themselves and maybe didn't have the ability to get it up as high into the air.
As you can see from the two sets of designs, you have an option for a very compact one operating on 40m and up, or go for the full 80m one which is the design that's going to be put into effect for MSARS.
From what I have found so far the tuning especially on its lowest frequency of operation does change with respect to height above ground - and as you move it up, the resonant frequency goes down.
It is possible to buy this design as a ready-made antenna, but you can build it yourself - all that's needed is the wire as detailed on the right plus the matching transformer.
* The schematic on the left (click to enlarge) is for a 49:1 transformer. If you want to deploy the 64:1 version, you simply require two more turns on the secondary winding, one on each side of the 'crossover'. For moderate power levels, you can just use 1 x FT240-43 mix toroid, or scale with more toroids of differing mixes as you see fit.
Steve Ellington N4LQ has done much research in recent years, and has produced several excellent YouTube videos on the subject, including this one:
He also started a great Facebook group which has really moved the EFHW discussion on leaps and bounds IMO. It can be found here:
[* Inserted by M0XYF]
If there is anything you need to know about this - please contact me.
73 Phil G4UDU