diff --git a/README.md b/README.md
index fb057e8..5c71ae4 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,8 @@ Please also select a high quality receiver which fits to the PCB design (RXB6, S
 
 The PCB also allows the connection of a standard OLED device (SSD1306) to show the current apparent wind speed. But this is optional.
 
+The voltage regulator (7805) may require additional cooling (90 mA * 9 Volt = 0,81 Watt). An alternative is the following replacement which has the same pin layout as the 7805: https://www.digikey.de/product-detail/en/w-rth-elektronik/173950578/732-8243-5-ND/5725367?cur=EUR&lang=en
+
 A standard 4 button 433 MHz KeyFob is used to send (+1 / -1 degree) and (+10 / -10 degrees) course changes to the autopilot.
 The used Seatalk codes are derived from Thomas Knauf (http://www.thomasknauf.de/rap/seatalk2.htm ). Many thanks for this excellent piece of work.