diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6a39c2030..03dc1a977 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -388,7 +388,6 @@ set (wsjt_FSRCS
   lib/slope.f90
   lib/smo.f90
   lib/smo121.f90
-  lib/smolorentz.f90
   lib/softsym.f90
   lib/softsym9f.f90
   lib/shell.f90
diff --git a/lib/decode65a.f90 b/lib/decode65a.f90
index 704da79f5..714966e4e 100644
--- a/lib/decode65a.f90
+++ b/lib/decode65a.f90
@@ -13,7 +13,6 @@ subroutine decode65a(dd,npts,newdat,nqd,f0,nflip,mode65,ntrials,     &
   complex cx1(NMAX/8)                !Data at 1378.125 sps, offset by 355.3 Hz
   complex c5x(NMAX/32)               !Data at 344.53125 Hz
   complex c5a(512)
-  real s1a(-255:256,126)
   real s2(66,126)
   real a(5)
   logical first
@@ -84,18 +83,23 @@ subroutine decode65a(dd,npts,newdat,nqd,f0,nflip,mode65,ntrials,     &
 
   call timer('dec65b  ',0)
   qualbest=0.
+  minsmo=0
   maxsmo=0
-  if(mode65.ge.2) maxsmo=3
+  if(mode65.ge.2) then
+     minsmo=nint(width/df)
+     maxsmo=2*minsmo
+  endif
   nn=0
-  do ismo=0,maxsmo
+  do ismo=minsmo,maxsmo
      if(ismo.gt.0) then
-        w=width/df
-        if(ismo.eq.2) w=1.414*w
-        if(ismo.eq.3) w=2.0*w
         do j=1,126
-           call smolorentz(s1(-255,j),512,w,s1a(-255,j))
+           call smo121(s1(-255,j),512)
+           if(j.eq.1) nn=nn+1
+           if(nn.ge.4) then
+              call smo121(s1(-255,j),512)
+              if(j.eq.1) nn=nn+1
+           endif
         enddo
-        s1=s1a
      endif
 
      do i=1,66
@@ -126,6 +130,8 @@ subroutine decode65a(dd,npts,newdat,nqd,f0,nflip,mode65,ntrials,     &
      endif
   enddo
 
+!  print*,width,minsmo,maxsmo,nsmo,nn
+
   if(nft.eq.2) then
      decoded=decoded_best
      qual=qualbest