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@@ -1,6 +1,8 @@
 # picoAM
 A simple but capable AM transmitter for the Raspbery Pi pico!
 
+## USE Arduino Mbed OS RP2040 Boards VERSION 3.x! 4.x+ is not currently compatible.
+
 ![Image of assembled circuit](https://media.discordapp.net/attachments/1077080199847489626/1102196399577247774/20230430_133433.jpg)
 (image deviates slightly from current version of the circuit, apologies!)