diff --git a/acquire-beidou-b1cd.py b/acquire-beidou-b1cd.py
index 149e3b6..2ad7b4c 100755
--- a/acquire-beidou-b1cd.py
+++ b/acquire-beidou-b1cd.py
@@ -44,7 +44,7 @@ def search(x,prn):
 
 # parse command-line arguments
 # example:
-#   ./acquire-beidou-b1cd.py data/gps-5001-l1_a.dat 69984000 -9334875
+#   ./acquire-beidou-b1cd.py /dev/stdin 69984000 -9334875
 
 filename = sys.argv[1]        # input data, raw file, i/q interleaved, 8 bit signed (two's complement)
 fs = float(sys.argv[2])       # sampling rate, Hz
diff --git a/acquire-beidou-b1cp.py b/acquire-beidou-b1cp.py
index 471cc7c..b6ca75a 100755
--- a/acquire-beidou-b1cp.py
+++ b/acquire-beidou-b1cp.py
@@ -44,7 +44,7 @@ def search(x,prn):
 
 # parse command-line arguments
 # example:
-#   ./acquire-beidou-b1cp.py data/gps-5001-l1_a.dat 69984000 -9334875
+#   ./acquire-beidou-b1cp.py /dev/stdin 69984000 -9334875
 
 filename = sys.argv[1]        # input data, raw file, i/q interleaved, 8 bit signed (two's complement)
 fs = float(sys.argv[2])       # sampling rate, Hz
diff --git a/acquire-galileo-e1c.py b/acquire-galileo-e1c.py
index ddbe168..aa05113 100755
--- a/acquire-galileo-e1c.py
+++ b/acquire-galileo-e1c.py
@@ -44,7 +44,7 @@ def search(x,prn):
 
 # parse command-line arguments
 # example:
-#   ./acquire-galileo-e1c.py data/gps-5001-l1_a.dat 68873142.857 -8662285.714
+#   ./acquire-galileo-e1c.py /dev/stdin 69984000 -9334875
 
 filename = sys.argv[1]        # input data, raw file, i/q interleaved, 8 bit signed (two's complement)
 fs = float(sys.argv[2])       # sampling rate, Hz
diff --git a/acquire-glonass-l3q.py b/acquire-glonass-l3q.py
index a69d4be..80365b9 100755
--- a/acquire-glonass-l3q.py
+++ b/acquire-glonass-l3q.py
@@ -43,7 +43,7 @@ def search(x,prn):
 
 # parse command-line arguments
 # example:
-#   ./acquire-glonass-l3q.py /dev/stdin 68873142.857 -3255000.000
+#   ./acquire-glonass-l3q.py /dev/stdin 69984000 10383375
 
 filename = sys.argv[1]        # input data, raw file, i/q interleaved, 8 bit signed (two's complement)
 fs = float(sys.argv[2])       # sampling rate, Hz