28MHz Rubber Duck

The main component in this design is the supporting rod, which the wire is wound upon. The former is 530mm for the antenna proper and 9mm diameter, plus about 15mm, which is inserted into a PL259 for RG8 style coaxial cable. 1mm 7/02 insulated wire was used.

Construction of the antenna.

I've managed to work around Europe with 5 watts when down at the beach using this antenna. I cannot really class this is a practical antenna because it's too rigid, and mounting it on the BNC socket on the front of the rig is asking for trouble. One knock and you'll probably damage the aluminium chassis inside.

Can you guess who found this out the hard way ? The antenna is high Q and the tuning can vary depending upon how you hold the rig and movement of the microphone cable etc. To achieve the best match, you only need to snip off 5mm at a time. Bandwidth is OK to cope with typical band use.

Conclusion. The antenna works, and maybe a different construction could make it practical but as it stands it's more of academic interest for me.

I did make an 18Mhz version using the same 530mm former. Yes it worked and I made contacts with it, but was even more a high Q antenna.

It does at least illustrate the difficulties that need to be overcome (if indeed possible) to make these antennas practical but it was a good learning exercise.