I have finished the installation of 2 two directional beverage following the
design in ON4UN 5th edition chapter 7-89 Fig 7-118 - I cannot get the
reflection transformer T3 to give the same gain as the other end of the
beverage at T1 - I have put the aim 4170 on the feed point of T1 and obtain 1.2
on one beverage and 1.3 on the other - playing around with the turns ratio I
can improve on these readings. When I look at the return signal being sent back
along the coax the SWR is almost perfect the band noise are approximately 50%
of the other direction. I have remade all the transformers using different
cores and built 2 controllers - the only thing I have not changed is the coax
and of course the ground. The other test I have not tried is to put a receiver
at the reflection transformer end see what the output is before its send back
along the coax. I have also reversed the windings of the reflection
transformer. I am using 2873000202 cores - the
reflection transformer is 3 turns and 7 turns which show around 120uh and
820uh depending on the core the coax is 75 ohm.
Dave RCQ
All good topband ops know fine whiskey is a daylight beverage.
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Topband Reflector
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