diff --git a/IO.cpp b/IO.cpp
index 8a76d4d..ea7b97b 100644
--- a/IO.cpp
+++ b/IO.cpp
@@ -323,6 +323,15 @@ uint8_t CIO::setFreq(uint32_t frequency_rx, uint32_t frequency_tx, uint8_t rf_po
   ((pocsag_freq_tx >= UHF2_MIN)&&(pocsag_freq_tx < UHF2_MAX)) ) )
     return 4U;
 
+  // Check banned frequency ranges
+  if( ((frequency_rx >= BAN1_MIN)&&(frequency_rx <= BAN1_MAX)) || ((frequency_tx >= BAN1_MIN)&&(frequency_tx <= BAN1_MAX)) || \
+  ((frequency_rx >= BAN2_MIN)&&(frequency_rx <= BAN2_MAX)) || ((frequency_tx >= BAN2_MIN)&&(frequency_tx <= BAN2_MAX)) )
+    return 4U;
+
+  if( ((pocsag_freq_tx >= BAN1_MIN)&&(pocsag_freq_tx <= BAN1_MAX)) || \
+  ((pocsag_freq_tx >= BAN2_MIN)&&(pocsag_freq_tx <= BAN2_MAX)) )
+    return 4U;
+
   // Configure frequency
   m_frequency_rx = frequency_rx;
   m_frequency_tx = frequency_tx;
diff --git a/IO.h b/IO.h
index 5fe4081..0159184 100644
--- a/IO.h
+++ b/IO.h
@@ -28,6 +28,7 @@
 #define LOW      0
 #define HIGH     1
 
+// HS frequency ranges
 #define VHF1_MIN  144000000
 #define VHF1_MAX  148000000
 #define VHF2_MIN  219000000
@@ -37,6 +38,12 @@
 #define UHF2_MIN  842000000
 #define UHF2_MAX  950000000
 
+// Banned amateur frequency ranges (satellite only, ISS, etc)
+#define BAN1_MIN  145800000
+#define BAN1_MAX  146000000
+#define BAN2_MIN  435000000
+#define BAN2_MAX  438000000
+
 #define SCAN_TIME  1920
 #define SCAN_PAUSE 20000