Here are some images and notes on the 2-wire Beverage receiving antenna at AI2Q.
(1) This image shows one of the cross-arms suspended from some handy trees.
(2) Here's a representation of the wavefront effect.
(3) This diagram shows the switchable bi-directional characteristic of the antenna.
(4) Here's the actual far-end termination autotransformer electrical information.
Transformer T3 is wound on an MN80-CX toroidal core, as are the other transformers in the system.
(5) This schematic shows the actual near-end electrical configuration. Note the use of an autotransformer at T2. This configuration for T2 makes it easier to wind the core.
Antenna direction selection (E or W) is accomplished using a SPST 12-V relay. It's powered through the signal coax. An extra SO-239 coaxial cable jack can route signals to a separate feedline in the future to implement a shack-located null-phaser network.
(6) The control box for the bias-T is mounted at the operating position. The phono plug (gray wire) activates a relay in my Omni-V transceiver that bypasses its T/R switch. The black phone plug feeds 12-V into the control box. One SO-239 feeds the Omni-V's receiver port. A second SO-239 can route an identical output signal to an auxilliary receiver. The third connector accepts signals from the near-end termination box mounted in the woods.
(7) This is the bias-T electrical configuration of the control box.
(8) Here's the near-end termination box in the woods. The extra wire flip-flopped on the "cold" end of the egg insulators permits loosening the main wires if field splices need to be made.
(9) Here's the far-end termination box.
(10) Here's a look-see inside the weatherproof far-end termination box.
(11) This plot shows typical performance for 1-wavelength and 2-wavelength operation.
(12) Here's a typical elevation plot.
(13) Hot diggety dog! Smokey, the ol' Second Op at AI2Q (now a Silent Woof), was happy that it worked!
That's all folks!
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