diff --git a/lib/superfox/sfox_sync.f90 b/lib/superfox/sfox_sync.f90
index 646f94aa6..4768b1bb8 100644
--- a/lib/superfox/sfox_sync.f90
+++ b/lib/superfox/sfox_sync.f90
@@ -23,7 +23,7 @@ subroutine sfox_sync(iwave,fsample,isync,f,t)
   ftol=20.0
   ia=nint((fsync-ftol)/df)
   ib=nint((fsync+ftol)/df)
-  lagmax=1.0/dtstep
+  lagmax=1.5/dtstep
   lag1=-lagmax
   lag2=lagmax
 
@@ -61,8 +61,6 @@ subroutine sfox_sync(iwave,fsample,isync,f,t)
   enddo
   savg=savg/jz
 
-!###
-
   ccfbest=0.
   ibest=0
   lagpk=0
@@ -106,11 +104,20 @@ subroutine sfox_sync(iwave,fsample,isync,f,t)
 !  write(*,4100) ibest,lagbest,f,dxi*df,t,dxj*dtstep
 !4100 format(2i6,2f10.1,2f10.3)
 
-!  print*,'aaa',ibest,lagbest
-!  do lag=lag1,lag2
-!     write(51,3051) lag*dtstep,ccf(ibest,lag)
-!3051 format(2f12.4)
-!  enddo
+  nsum=0
+  sq=0.
+  do lag=lag1,lag2
+     if(abs(lag-lagbest).gt.3) then
+        sq=sq + ccf(ibest,lag)**2
+        nsum=nsum+1
+     endif
+     write(51,3051) lag*dtstep,ccf(ibest,lag)
+3051 format(2f12.4)
+  enddo
+
+  rms=sqrt(sq/nsum)
+  snrsync=ccf(ibest,lagbest)/rms
+!  print*,'snr:',snrsync
 
   return
 end subroutine sfox_sync
diff --git a/lib/superfox/sfoxtest.f90 b/lib/superfox/sfoxtest.f90
index 15725f34f..b1d9b786a 100644
--- a/lib/superfox/sfoxtest.f90
+++ b/lib/superfox/sfoxtest.f90
@@ -13,6 +13,7 @@ program sfoxtest
   integer isync(44)
   integer jsync(171)
   integer itone(171)
+  integer nsb(10)
   real*4 xnoise(NMAX)                    !Random noise
   real*4 dat(NMAX)                       !Generated real data
   complex cdat(NMAX)                     !Generated complex waveform
@@ -39,6 +40,8 @@ program sfoxtest
             116, 122, 130, 131, 134, 136, 137, 140, 146, 154,  &
             159, 161, 163, 165/
 
+  data nsb/1,2,4,7,11,16,22,29,37,39/
+
   nargs=iargc()
   if(nargs.ne.11) then
      print*,'Usage:   sfoxtest  f0   DT  ITU M  N   K NS v hs nfiles snr'
@@ -83,11 +86,13 @@ program sfoxtest
   call sfox_init(mm0,nn0,kk0,itu,fspread,delay,fsample,ns0)
   tsync=NSYNC/fsample
   txt=(NN+NS)*NSPS/fsample
+  nstype=nv/10
+  nv=mod(nv,10)
 
-  write(*,1000) MM,NN,KK,NSPS,baud,bw,itu,tsync,txt
+  write(*,1000) MM,NN,KK,NSPS,baud,bw,itu,tsync,txt,nstype
 1000 format('M:',i2,'   Base code: (',i3,',',i3,')   NSPS:',i5,   &
           '   Baud:',f7.3,'   BW:',f9.3/                   &
-          'Channel: ',a2,'   Tsync:',f4.1,'   TxT:',f5.1/)
+          'Channel: ',a2,'   Tsync:',f4.1,'   TxT:',f5.1,'   SyncType:',i2/)
 
 ! Allocate storage for arrays that depend on code parameters.
   allocate(s3(0:NQ-1,0:NN-1))
@@ -103,25 +108,33 @@ program sfoxtest
   allocate(correct(0:NN-1))
 
   idum=-1
-  jsync=0
-  jsync(1)=1
-  jsync(NDS)=1
-  ms=2
-  do i=1,100000
-     j=1 + (NDS-1)*ran1(idum)
-     if(jsync(j).eq.0) then
-        jsync(j)=1
-        ms=ms+1
-        if(ms.eq.NS) exit
-     endif
-  enddo
-  j=0
-  do i=1,NDS
-     if(jsync(i).eq.1) then
-        j=j+1
-        isync(j)=i
-     endif
-  enddo
+  if(nstype.eq.2) then
+     jsync=0
+     jsync(1)=1
+     jsync(NDS)=1
+     ms=2
+     do i=1,100000
+        j=1 + (NDS-1)*ran1(idum)
+        if(jsync(j).eq.0) then
+           jsync(j)=1
+           ms=ms+1
+           if(ms.eq.NS) exit
+        endif
+     enddo
+     j=0
+     do i=1,NDS
+        if(jsync(i).eq.1) then
+           j=j+1
+           isync(j)=i
+        endif
+     enddo
+  else if(nstype.eq.3) then
+     isync(1:10)=nsb
+     isync(11:20)=nsb + isync(10) + 2
+     isync(21:30)=nsb + isync(20) + 2
+     isync(31:40)=nsb + isync(30) + 2
+     isync(41:44)=nsb(1:4) + isync(40) + 2
+  endif
 
   rms=100.
   baud=fsample/nsps                 !Keying rate, 11.719 baud for nsps=1024