diff --git a/direwolf/direwolf-transmit-dtmf-aprs.conf b/direwolf/direwolf-transmit-dtmf-aprs.conf
index 786102cd..37ddbe97 100644
--- a/direwolf/direwolf-transmit-dtmf-aprs.conf
+++ b/direwolf/direwolf-transmit-dtmf-aprs.conf
@@ -1,4 +1,5 @@
 ADEVICE hw:CARD=Loopback,DEV=0 hw:CARD=Headphones,DEV=0 
+PTT GPIO 20  
 MYCALL AMSAT
 CHANNEL 0
 MODEM 1200