This antenna has a coil in the antenna wire at a distance of 10mtr.
Excellent radiation efficiency due resonant design and low loss parts.
Loss in Matching unit < 0,8dB on 10mtr < 1,5dB.
With a vent plug.
EQUALIZING PRESSURE USING MEMBRANE VENTS IMPROVES ENCLOSURE SEAL PERFORMANCE, Protect seals on sensitive electronics against water, dust, dirt and liquids with rapid pressure equalization. Block contaminants such as dirt, dust or salts in changing environmental conditions. Rapidly equalize pressure also helps virtually eliminate condensation and reduce housing design complexity.
I live close to the centre of Guildford and have a "postage-stamp" garden. Connected one end of the antenna just below the roof and ran the wire as a "sloper" down to the garden fence.On the air on 3 bands and couldn't be happier. A quality product.
Great antenna use the 3 bander as a sloppier while operating portable 16ft high down to 5ft
Good match on the 3 bands will tune other bands with auto atu. Getting good reports back and worked many Dx stations. Also use the 5 band hyendfed as my base station can not fault it ,only 18ft high and dog legged as we only have small garden can recommend these antennas it was a replacement for a butternut.Have been using them for about 8 months