I've been using an open-wire fed rotary dipole that is a halfwave on 20 meters on all bands from 40 through 10 meters for the past 4 years or so. The feeding/matching system has gone through various iterations, but now uses homemade open-wire line of no. 12 wire (2 mm) spaced 4.5 inches (11.4 cm), a very slightly modified Johnson kW Matchbox, and a pair of inductors for reactance cancellation on 30 meters. The line is about 34 feet long (10.4 m). The SWR on the worst band (7 MHz) approaches 100:1, but losses calculated by TLW are around 1 dB or less.

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
CWops no. 5
http://www.qsl.net/k2vco/
On 7 Jan 2019 00:15, K9MA wrote:
The really attractive thing about open line, and even window line, is that its loss is so low you can use it at a very high SWR, and take care of the matching at the station end. This is especially useful for multi-band antennas. The famous G5RV, for example, will work just exactly the same fed with window line and a tuner as it will with the usual matching section.

73,
Scott K9MA
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