Friday, January 8, 2016

RX ANT Switching box, part 3 - antenna distributor - triplexer + splitter







After:


  there is another part of my RX antenna switching box. Today the RX antenna distributor. It consists of LC circuit for each band and rx splitter (magic T). This board allows you to split one beverage into 2 RX for each band. Or single RX on some or all bands - relay bypass.
   Each splitter is isolated by LC resonance circuit. That works with low insert loss at resonant frequency but with high impedance out of it. This is necessary because you need to isolate impedance of the splitter. If you do not use it and connect three splitters together, you obtain 50 / 3 ohm = 17 ohm for antenna input. Look at measurement for each band with and without splitter. Btw this simply LC circuit has nice paramaters out of designed band...

Board

Schematic diagram

Table mess :)


40m with splitter
40m just LC
80m just LC
160m with splitter
160m just LC

Splitter INPUT S11

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