Supercharged Active Phaser-Combiners

Dallas Lankford, 1/12/2012

The diagram and schematic above depicts a supercharged phaser-combiner for dual flag (including delta flag and other
variant shapes of the flag antenna) arrays. Testing of this approach is not complete, and for that reason it is not known if the
common mode chokes following the SFF's are necessary (it may depend on the size of the antenna elements, spacing of the
elements, and other design parameters.

For dual flag arrays which are not too small, this approach is equivalent (wrt signal output) to placing FET followers at the
antenna elements. The fly in the ointment is whether enough common mode chokes can be used to sufficiently reduce lead
in pick up. Placing FET followers at the antenna elements will produce better signal to noise ratios only when the signal
output of the flag elements is so low that sufficiently reducing signal pick up by the lead in is impractical or impossible.
Exactly how to extend this result to other types of arrays (non-flag arrays) is presently an open question.

The “step down at flag antenna element – 100' twinax – step up (by same amount as stepped up) – FET follower”
configuration was tested a few minutes ago (1/12/2012 evening) and it had the same gain as the “FET follower at the flag
element – 100' twinax”. This established that a FET follower need not be placed at the antenna element, but can be placed
inside our house at the input of the phaser-combiner (provided signal levels are high enough and twinax pick up is low
enough). In fact, it appears that the FET follower, common mode chokes, and phaser combiner can all be put inside a single
RF tight box,

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