diff --git a/sensor433/.gitignore b/sensor433/.gitignore
index 89cc49c..64727e5 100644
--- a/sensor433/.gitignore
+++ b/sensor433/.gitignore
@@ -3,3 +3,4 @@
 .vscode/c_cpp_properties.json
 .vscode/launch.json
 .vscode/ipch
+config.h
\ No newline at end of file
diff --git a/sensor433/README.md b/sensor433/README.md
index f5bde8b..740c6bb 100644
--- a/sensor433/README.md
+++ b/sensor433/README.md
@@ -2,5 +2,8 @@
 
 ![fritzing](sensor_Steckplatine.png)
 
+# Build
+Copy config.h.example to config.h and set your project specific settings there.
+
 # flash attiny with minipro on linux and the TL866II plus after compiling:
   minipro -p attiny85 -w .pio/build/attiny85/firmware.hex
\ No newline at end of file
diff --git a/sensor433/platformio.ini b/sensor433/platformio.ini
index 61af260..01e5dce 100644
--- a/sensor433/platformio.ini
+++ b/sensor433/platformio.ini
@@ -26,7 +26,11 @@ upload_speed = 19200
 ; http://eleccelerator.com/fusecalc/fusecalc.php?chip=attiny85
 board_build.f_cpu = 8000000L
 
-force_verbose = true
+force_verbose = True
+; set environment variables in a python script for project specific settings
+; does not work because variables not available in build!
+; extra_scripts =
+;  pre:env.py
 
 ; Platformio Project Tasks -> Set Fuses!
 board_fuses.lfuse = 0xE2
diff --git a/sensor433/src/config.h.example b/sensor433/src/config.h.example
new file mode 100644
index 0000000..fbf4a5f
--- /dev/null
+++ b/sensor433/src/config.h.example
@@ -0,0 +1,5 @@
+#ifndef __CONFIG_H__
+#define __CONFIG_H__
+
+
+#endif
\ No newline at end of file
diff --git a/sensor433/src/main.cpp b/sensor433/src/main.cpp
index e575fce..542f9c8 100644
--- a/sensor433/src/main.cpp
+++ b/sensor433/src/main.cpp
@@ -59,6 +59,10 @@
 #include "dht22.h"
 dht22 dht;
 
+
+// Configuration, see file config.h.example and rename to config.h. Project specific, do not add to git!
+#include "config.h"
+
 #define RH_BUF_LEN 11
 uint8_t rh_buf[RH_BUF_LEN] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};