K9AY loops

The K9AY is terminated loop. It consists of a wire loop of any convenient shape (diamond, delta, etc), hung from a single support and with a ground rod at the bottom. A 9:1 impedance-matching transformer is connected from one end of the loop to the ground and terminating resistor is connected the other end of the loop to the ground. This antenna is directional. Favoring signals are arriving from the feed point end. You can also change the antenna far field by changing RLOAD (RTERM) of the loop.

Main functions:

• RX antenna
  • Broadband
  • 4 directions
  • Needs small room
  • Great for portable operations
  • 50/75 ohm feed line version
  • Good for phasing more pieces into the array
• Two versions
  • Variable load resistor - VARIABLE RLOAD * from version 3.1, also FIXed RLOAD on PCB with Jumper select
  • Fixed load resistor - FIXed RLOAD
• ONLY FEEDER! WITHOUT CONTROLLER! This controller could be use.
• Common-mode coax choke icluded.
• Common-mode controller cable choke icluded.
• High voltage electrostatic protection with neon lamps.
• High power IN/OUT protection with PTC.
• Controlled by DC voltage on connector or over coax feed line. More
• Stainless connections screws.
• Quality PTFE SO-239 connector.
• IP56 box.
• Size 10x10 cm (feeder).
• Available as
  • Assembled
  • KIT - all parts + PCB + box
  • PCB

Fixed

Variable

New SMD version since 3/2022

Download

K9AY
Manual in WiKi		WiKi manual
Antenna loop design examples		WiKi loop design
YOUTUBE videos		YouTube
rev 3.1		variable.sch	pcb	eagle684
rev 2.4		variable.sch	pcb	eagle684
rev 0.1	fixed.sch	variable.sch	pcb	eagle466
CONTROLLER DC example		DC controller example
CONTROLLER ACDC example		AC/DC controller example
We believe open source is a better way of doing things. View and download the Shield Schematic and PCB Kicad/Eagle CAD files, LibreCAD .DXF, or Inkscape .SVG files. The hardware designs are released under the Attribution-NonCommercial 2.0 Generic

Users implementation photos

by F1SRC

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