RX antenna - K9AY loops switch with remotly VARIABLE Rload
This revision is from 2016/06/29 21:22. You can Restore it.
Assembled KIT
The drill drawing
Paste the drawing on the box and fix it with some tape.
Schematic diagram
Voltage controlled resistor
- insert VAC plus to plus - check package
Protection diodes
- solder 5 + 5 diodes
- these diodes protect Rload resistor against high power, electrostatic etc.
Insert rest parts
TRANSFORMERS winding - very important thing!
- for 50 ohm coax feed line : 2 turns on primar (coax) and 6 turns on secondar side (loop)
- for 75 ohm coax feed line : 2 turns on primar (coax) and 5 turns on secondar side (loop)
Front side
Front side
Common-mode coax choke
Wind the coax
- Wind the coax as is on the picture, there should be 7 or 8 turns.
- fix it by one binder and use second one to fix choke to the PCB