May 22, 2005

double spiral antenna


I've been trying to find out how to make one of these for months.

I first read about them - broadband double spiral antennas - in a book by William Lonc. The attraction, apart form the beautiful interlocked double spiral form, is that the antenna covers a wide range of frequencies.

The Lonc reference was tantalising. Despite searching high and low I couldn't find the details as to how to make one anywhere, until Mike Jones gave me the formula the other day.

It's a bit wonky. Quite hard to bend the copper pipe. Plus the pipe ran out 6 inches from the end.

Posted by Jem Finer at May 22, 2005 7:20 PM