🔘For many years the 🗼antenna which I have been using for my amateur radio activities on long-wave and medium-wave bands ( 2190m & 630m ) has been a vertical, tubular aluminium pole connected at its top to a horizontal wire. Both the pole and the wire together form the antenna element; the familiar 'inverted-L' configuration |''''''''''''''' . There is a picture of it during construction in the post dated 11.09.2012.
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| Vertical section of the antenna - the storage box at the base |
However, I also wanted to use the antenna on the 160m band ( 1810 - 2000KHz ); but it wasn't resonant ( less than half-wavelength long ) on that band and also presented a severe impedance mismatch to the 50 Ohm coax cable which connected it to the transmitter.
I solved the non-resonance and mismatch problems by making an L-C "L-Match" network inside a storage box and connecting it to the antenna's vertical pole at ground level; see image below - the cover has been removed to show the ➿coil (L), capacitor -∥- (C), coax cable and wire interconnections.
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| L-Match network installed at the base of the antenna |
After a very short time spent adjusting the variable coil and variable capacitor I was able to obtain a perfect match to the coax at the point of connection to the antenna on my chosen frequency ∿1840KHz, although the antenna does exhibit a very narrow bandwidth.
After using the modified antenna 🗼 for just a few evenings, I have contacted 18 countries on 160m band.🔘
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