Antenna one to two STACK MATCH with BiP/BoP function by OK2ZAW

Can be controlled by:

remoteqth server band-decoder order
Stack Match is designed for the stack of antennas - do matching and power splitting to
two antennas. This Stack Match allows any of the four combinations for: upper - lower - Both In Phase(BIP) or Both Out Phase(BOP) antennas, vertically shaping the radiation lobes and changing the radiation take-off angle to optimize the signals depending on the varying ionospheric propagation angles.
Could be controlled independently for RX and TX - depends on controller.
Works with Mono-band antennas as well as Tri-band and Multi-band antennas! ( if wide band phase transformer is used )

Main functions:

Compare antennas:

There is comparison of the four combinations of a stack of two five element Yagi antennas. The possible combinations are as follows:
  • TOP antenna in 30m / 99ft - BLACK color.
  • BOTTOM antenna in 15m / 50ft - RED color.
  • BIP - Both IN Phase antennas in 15/30m - 50/90ft - BLUE color. Second picture: BLACK color.
  • BOP - Both OUT Phase antennas in 15/30m - 50/90ft - GREEN color. Second picture: RED color.

  • Top - Bottom - Both In Phase
    and Both Out of Phase

    Both In Phase
    and Both Out of Phase


    Four versions: ( MP / HP and internal / external PH shifter )
    Power handling * < 3 kW < 5 kW
    Frequency range ** 1,8-50 MHz 1,8-50 MHz
    Characteristic impedance 50 ohm 50 ohm
    Relay version 5 , 12 or 24 V 5 , 12 or 24 V
    PCB thickness 2 mm 2 mm
    The measured values: ( stack match optimized for 10-20m bands )



    ANT1 + ANT2 BIP

    ANT1 + ANT2 BOP
    (internal WB PH shifter)
    *) Normal CW, SSB, RTTY DX operation. In contest mode: CW, SSB 75% and RTTY 50% of HF power.

    **) Usually optimized for some bands. For example for 6m, 10-15-20m or 160-80-40, but it could be designed for all bands with some compromise.

    Matrix table

    Stack match Inputs
    Selected A1 A2 Bal PH
    A1 + - - -
    A2 - + - -
    BIP + + + -
    BOP + + + +
    + 12 or 5V / - NC


    Stack match
    Version 7 pcb sch eagle92
    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

    Laurent FM5BH

    his web!

    Laurent FM5BH

    Imre HA9AX

    Imre HA9AX