diff --git a/CalPOCSAG.cpp b/CalPOCSAG.cpp
index 2629d41a..bf88a510 100644
--- a/CalPOCSAG.cpp
+++ b/CalPOCSAG.cpp
@@ -20,13 +20,6 @@
 #include "Globals.h"
 #include "CalPOCSAG.h"
 
-// POCSAG 600 Hz Square Wave Test Pattern
-q15_t square600Hz[] = {
-          950,  950,  950,  950,  950,  950,  950,  950,  950,
-          950,  950,  950,  950,  950,  950,  950,  950,  950,
-         -950, -950, -950, -950, -950, -950, -950, -950, -950,
-         -950, -950, -950, -950, -950, -950, -950, -950, -950,
-         };
 
 CCalPOCSAG::CCalPOCSAG() :
 m_state(POCSAGCAL_IDLE)
@@ -39,14 +32,10 @@ void CCalPOCSAG::process()
     return;
 
   uint16_t space = io.getSpace();
-  if (space <= 205U)
+  if (space <= 165U)
     return;
 
-  io.write(STATE_POCSAG, square600Hz, 40U);
-  io.write(STATE_POCSAG, square600Hz, 40U);
-  io.write(STATE_POCSAG, square600Hz, 40U);
-  io.write(STATE_POCSAG, square600Hz, 40U);
-  io.write(STATE_POCSAG, square600Hz, 40U);
+  pocsagTX.writeByte(0xAAU);
 }
 
 uint8_t CCalPOCSAG::write(const uint8_t* data, uint8_t length)
diff --git a/POCSAGTX.h b/POCSAGTX.h
index 8cd75f7a..d640862e 100644
--- a/POCSAGTX.h
+++ b/POCSAGTX.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015-2019 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -29,6 +29,8 @@ class CPOCSAGTX {
 
   uint8_t writeData(const uint8_t* data, uint8_t length);
 
+  void writeByte(uint8_t c);
+
   void process();
 
   void setTXDelay(uint8_t delay);
@@ -45,8 +47,6 @@ class CPOCSAGTX {
   uint16_t             m_poLen;
   uint16_t             m_poPtr;
   uint16_t             m_txDelay;
-
-  void writeByte(uint8_t c);
 };
 
 #endif