Staggered Beverage
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Staggered beverage 300m
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Single beverage 300m
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3D plots (oriented at 320° as it is set up here)
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Structure of the staggered beverages oriented at 320° angle as installed here
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Horizontal field plot overlaid onto the map to demonstrate what is achieved
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LW properties
An interesting feature can be observed on LW. Changing the phase slightly worsens the F/B but moves the null around. This 3D-plot is for 207kHz and the phase is set so that DLF from the south east is dramatically reduced that Iceland from the north-west becomes audible even during local noon. I tried it on all other LW channels and all could be nulled |
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Switching combiner inputs
When exchanging both antenna inputs of the combiner the main direction should be switched by 180°. This can be observed for example on 810 kHz. The strong BBC Scotland is reduced and Makedonija becomes audible at night. However the 3D-plot shows a a far less ideal pattern. Nevereless it only requires a relay and why not use this feature during live seesions. Altering the phase will also move around the null a bit |
· | Both antennas need to be absolute identical and have identical termination resistors and ground rod resistance.
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· | They have to deliver the exact same signal, the only one difference should be the phase shift
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· | Both antennas have to have 50 ohms impedance to prevent any impedance transformation caused by the 50 ohm coax
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Staggered structure with combiner block diagram
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Combiner board (top side)
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Combiner board (bottom side)
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The board is connected to the Ant-Selector |