diff --git a/direwolf/direwolf-pacsatsim-pwm-loopback.conf b/direwolf/direwolf-pacsatsim-pwm-loopback.conf
index 2dc8d9eb..87a3ee6a 100644
--- a/direwolf/direwolf-pacsatsim-pwm-loopback.conf
+++ b/direwolf/direwolf-pacsatsim-pwm-loopback.conf
@@ -1,5 +1,5 @@
 ADEVICE shared_mic plughw:CARD=Loopback,DEV=0 
-PTT GPIOD gpiochip0 -27  
+PTT GPIOD gpiochip0 27  
 MYCALL AMSAT-12
 CHANNEL 0
 MODEM 1200