Today the weather was ideal for some /p over Hornchurch Country Park.
85Ah Battery, Icom 7200, 18m Roach Pole, Inductor 340µH.
The roach pole provided 18m (60ft) of antenna, and when coupled with the inductor at 15m provided a match at 1830 kHz. The ATU was used to provide a match at 1910 kHz, the club top band frequency. It makes it all a bit critical having the inductor so high, but the big advantage is that the bottom 15.5 metres has a lot of current in it, leaving only the 2.5 metres above it at a high impedance, making a better radiator. Ground was provided by a chicken wire fence, which I have used many times before with good results.
Below is a short video showing the antenna first on 24MHz where Dave is working Bahrain with the vertical set up close to a ⅝ wave, then afterwards, it’s fully extended with the loading coil 15.5 metres up, making it a loaded ¼ wave for 160m. The antenna was resonant at 1830kHz, a bit low, so the ATU was used. I calculated for 1900kHz, so I guess 70kHz off isn’t bad! It would be easy enough to fine tune it. Lovely day for it, a bit breezy towards the end though!