Geoff's Challenge 2010

For year 12 of Geoff’s challenges, Geoff came up with one of his most well supported challenges to date – a 20m portable, vertical antenna. 

 

Seven members rose to the challenge, with a variety of vertical antennas, large and small for the band.  Geoff was really pleased with the entries, and other members remarked that they were really impressed by the items entered for the challenge.   

 

Members were certainly resourceful pressing a variety of materials into service included everything from golf balls to kitchen chopping boards, via what looked like an old CD into service!  Everyone agreed that all the antennas they were all worthy entries, with several being used on the air during the evening.

 

Phil Ciotti G3XBZ submitted a 20m end-fed vertical based on the popular fibreglass fishing rod, complete with coil to reduce the overall length and matching arrangement at the base (seen in the photo on the right).

 

Phil used a heavy stand to support the fishing rod without the need for guy ropes.   

 

 

Alan Walker G4UWS had a 20m vertical antenna, based around a fibreglass fishing rod.

 

It was certainly sufficiently compact to be to be portable (photo on the left).  

 

 

Tex G1TEX produced a vertical that he had built for an exhibition station a few years previously.  Part of it can be seen in the photo on the right.

 

Colin G6MXL went for a ¼-wave vertical made from swaged aluminium poles.  3 x 1/4–wave radial wires were used. 

 

The poles simply slotted together and were supported by guy ropes looped through meat skewers with golf balls on top (to help find them in the undergrowth in the dark) back to the centre, enabling Colin to tie them off in the centre.

The centre of the coax was connected to the pole and the outer to the radial wires.  The antenna can be seen in the photo on the left.

 

 

 

Colin G0JII came up with a well-engineered 20m vertical antenna, made from copper pipe, making use of plumbing fittings.  This antenna can be seen in the photo on the right.

 

Eddie 2E0BVI chose a design using a capacity top-hat to reduce the overall length of the antenna.  It was one of the few antennas small enough to erect indoors.  Eddy’s antenna can be seen in the photo on the far right.

 

Les M0ARM showed an innovative design based around a plastic kitchen chopping board that was still work in progress.   

    

 

After a close vote, Eddie’s antenna was chosen as the winner, because it was the most compact and easy to transport and carry. 

 

Eddie is seen here accepting the trophy from Rob Mannion G3XFD, Editor of Practical Wireless.