"JSF" wrote in message
. ..
Anyone used one and if so how did it compare to a 1/4 wave.

I build one for 2 meters some years ago. The element was 1/4 copper tubing
with an air spaced variable at the end, and fed with a modified gamma match.
The antenna was about 3 inches tall, and it fit on top of my van without
hitting the garage on the way in.

I did one set of rough comparisons between it and a 1/4 wave mag mount
vertical. (A buddy gave readings from his S-meter) The vertical was better,
but by less than 3 dB. This was not really a good test, but probably
provided a valid assesment of which was better. However, the DDRR provided
quite acceptable service into the local repeater, and I used the antenna
until I sold the van.

--Wayne