diff --git a/lib/superfox/sfoxtest.f90 b/lib/superfox/sfoxtest.f90
index 70d84c73c..e46318452 100644
--- a/lib/superfox/sfoxtest.f90
+++ b/lib/superfox/sfoxtest.f90
@@ -25,10 +25,14 @@ program sfoxtest
   if(nargs.ne.10) then
      print*,'Usage:   sfoxtest  f0   DT  ITU M  N  K  sw nv nfiles snr'
      print*,'Example: sfoxtest 1500 0.15  MM 8 74 44 100  0   10   -10'
-     print*,'  LQ: Low Latitude Quiet'
-     print*,'  MD: Mid Latitude Disturbed'
-     print*,'  HM: High Latitude Moderate'
-     print*,'  ... etc.'
+     print*,'         f0=0 ==> f0, DT assume suitablels random values'
+     print*,'         LQ: Low Latitude Quiet'
+     print*,'         MM: Mid Latitude Moderate'
+     print*,'         HD: High Latitude Disturbed'
+     print*,'         ... and similarly LM LD MQ MD HQ HM'
+     print*,'         sw = width of Sync sweep, Hz'
+     print*,'         v=1 for .wav files, 2 for verbose output, 3 for both'
+     print*,'         snr=0 to loop over SNRs 0 to -20 dB'
      go to 999
   endif
   call getarg(1,arg)