M/M combine

The Open M/M combine by RemoteQTH.com is the black box designed for IG9Y contest group. This box allows you to share the MAIN antenna systems (MAIN OUT connector) for RX and TX to MAIN and SUB TRX. There is also PTT interlock build in. It could be use for both SO2R or MO2R operations.


Main features




Technical parameters:

Isolation Main-Sub (RX):		typ. 40dB (160m) / typ. 22dB (10m)
Isolation Main-main, Sub-FA:		typ. 90dB (160m) / typ. 60dB (10m)
Isolation Main TX, SubRX FA:		typ. 100dB (160m) / typ. 85dB (10m)
Isolation Main ANT4, SubTX:		typ. 85dB (160m) / typ. 62dB (10m)
Insert loss TX:				max. 0.08dB
Insert loss RX:				max. 3.4dB resp. 7dB (Main TRX , ANT4 enabled)
DC power consumption:		        +12 - 14 V DC, 1A + stack match consumption

Stack match configuratin examples:

Please follow pictures at One to Three stack match for some typical situations.

Isolation between RX ports Main-Sub

Main RX ATT for Main out (ANT4 enable)

Isolation tu Sub RX, Main is TXing

Main TXing, Sub RX from FA input

ATT for Sub RX, sharing MAIN out


Main board sch1 brd1 eagle185
sch2 brd2
Control box sch kicad180 Arduino code400
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