diff --git a/Makefile b/Makefile
index aa3d05d..91f4590 100644
--- a/Makefile
+++ b/Makefile
@@ -12,7 +12,7 @@
 MCU = atmega328p
 
 # Target file name (without extension).
-TARGET = images/MicroAPRS
+TARGET = images/MicroModemGP
 
 # Programming hardware: type avrdude -c ?
 # to get a full listing.
diff --git a/flash b/flash
index dbd6704..7591772 100755
--- a/flash
+++ b/flash
@@ -1,2 +1,2 @@
 #!/bin/bash
-avrdude -p $2 -c arduino -P /dev/tty$1 -b 115200 -F -U flash:w:images/MicroAPRS.hex
+avrdude -p $2 -c arduino -P /dev/tty$1 -b 115200 -F -U flash:w:images/MicroModemGP.hex
diff --git a/hardware/AFSK.h b/hardware/AFSK.h
index add4a8b..45e5643 100644
--- a/hardware/AFSK.h
+++ b/hardware/AFSK.h
@@ -42,8 +42,8 @@ inline static uint8_t sinSample(uint16_t i) {
 #define CONFIG_AFSK_RX_BUFLEN 64
 #define CONFIG_AFSK_TX_BUFLEN 64   
 #define CONFIG_AFSK_RXTIMEOUT 0
-#define CONFIG_AFSK_PREAMBLE_LEN 50UL
-#define CONFIG_AFSK_TRAILER_LEN 5UL
+#define CONFIG_AFSK_PREAMBLE_LEN 150UL
+#define CONFIG_AFSK_TRAILER_LEN 25UL
 #define BIT_STUFF_LEN 5
 
 #define SAMPLERATE 9600