Topband: 2 Direction reversable beverage using coax cable

David Cole g3rcq at yahoo.co.uk
Sun Apr 14 15:39:41 EDT 2013


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 


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