diff --git a/radio/src/CMakeLists.txt b/radio/src/CMakeLists.txt
index 95a437652..caa6a3615 100644
--- a/radio/src/CMakeLists.txt
+++ b/radio/src/CMakeLists.txt
@@ -152,6 +152,9 @@ elseif(PCB STREQUAL TARANIS)
   if(TARANIS_INTERNAL_PPM)
     add_definitions(-DTARANIS_INTERNAL_PPM)
   endif()
+  if(MIXERS_MONITOR)
+    add_definitions(-DMIXERS_MONITOR)
+  endif()
 elseif(PCB STREQUAL 9X OR PCB STREQUAL 9XR)
   set(ARCH AVR)
   set(MCU atmega64)