diff --git a/ferror.c b/ferror.c
index 05090bf..020119a 100644
--- a/ferror.c
+++ b/ferror.c
@@ -19,11 +19,11 @@ va_list arg_ptr;
     vfprintf(stderr, format, arg_ptr);
     va_end(arg_ptr);
 
-    fprintf(stderr, "\nNow terminating the program...\n");
-    fflush(stderr);
-
-    exit(5);
+    //    fprintf(stderr, "\nNow terminating the program...\n");
+    //    fflush(stderr);
 
+    //    exit(5);
+    return;
 }
 
 /* ===================================================================== */
diff --git a/frequencies.txt b/frequencies.txt
index 9c92076..8c6a972 100644
--- a/frequencies.txt
+++ b/frequencies.txt
@@ -326,3 +326,35 @@
 31797 2273.072
 35951 2272.842
 19822 2279.984
+39462 2242.505
+35951 2253.531
+35951 2254.555
+05560 2242.534
+39088 2243.334
+26958 2243.013
+40555 2280.006
+35938 2281.725
+35938 2280.701
+39210 2280.006
+27858 2232.711
+37849 2235.445
+39768 2235.006
+37391 2234.069
+24753 2235.450
+33434 2245.995
+38248 2246.006
+33434 2245.995
+33434 2245.995
+29522 2249.423
+39630 2247.384
+35951 2249.436
+35951 2247.388
+39630 2246.361
+39630 2248.409
+39630 2249.433
+40143 2248.555
+40298 2271.604
+25789 2264.989
+25476 2264.857
+40588 2215.993
+23802 2264.978
diff --git a/rffit.c b/rffit.c
index 65fcff7..c2a6dab 100644
--- a/rffit.c
+++ b/rffit.c
@@ -23,8 +23,8 @@ struct site {
 } site;
 struct point {
   char timestamp[24];
-  double mjd,freq,v;
-  float t,f;
+  double mjd,freq,v,freq0;
+  float t,f,res;
   float flux;
   int flag,site_id,rsite_id;
   struct site s,r;
@@ -464,7 +464,7 @@ int main(int argc,char *argv[])
       cpgbox("BCTSN",0.,0,"BTSN",0.,0);
       //      cpgenv(xmin,xmax,ymin,ymax,0,0);
       cpglab(xlabel,ylabel,"");
-      
+
       // Plot orbit
       if (satno>0 && plot_curve==1 && residuals==0) {
 
@@ -512,17 +512,16 @@ int main(int argc,char *argv[])
 	  cpgsci(1);
 	  cpgsls(1);
 	}
-      }
-
+      } 
       // Plot selected points
       for (i=0;i<d.n;i++) {
 	for (j=0;j<nsite;j++) 
 	  if (d.p[i].site_id==site_number[j])
 	    break;
-
+	
 	color=j+2;
 	style=17;
-
+	
 	x=d.p[i].t;
 	y=d.p[i].f;
 	if (d.p[i].flag==1) {
@@ -1421,7 +1420,8 @@ double compute_rms(void)
       } else {
 	f=(1.0-v/C)*d.ffit;
       }
-
+      d.p[i].freq0=f;
+      d.p[i].res=d.p[i].freq-f;
       rms+=pow(d.p[i].freq-f,2);
       n++;
     }
diff --git a/rfplot.c b/rfplot.c
index 1dc911a..006327c 100644
--- a/rfplot.c
+++ b/rfplot.c
@@ -20,7 +20,76 @@ void dec2sex(double x,char *s,int f,int len);
 void time_axis(double *mjd,int n,float xmin,float xmax,float ymin,float ymax);
 void usage(void);
 void plot_traces(struct trace *t,int nsat);
-struct trace locate_trace(struct spectrogram s,struct select sel,int site_id);
+struct trace fit_trace(struct spectrogram s,struct select sel,int site_id);
+
+// Fit trace
+struct trace locate_trace(struct spectrogram s,struct trace t,int site_id)
+{
+  int i,j,k,l,sn,w=100.0;
+  int i0,i1,j0,j1,jmax;
+  double f,fmin;
+  float x,y,s1,s2,z,za,zs,zm,sigma;
+  FILE *file;
+  char filename[64];
+  
+  sprintf(filename,"track_%05d_%08.3f.dat",t.satno,t.freq0);
+
+  // Open file
+  file=fopen(filename,"a");
+
+  fmin=(s.freq-0.5*s.samp_rate)*1e-6;
+
+  // Loop over trace
+  for (i=0;i<t.n;i++) {
+    // Skip when satellite is below the horizon
+    if (t.za[i]>90.0)
+      continue;
+    
+    // Compute position
+    y=(t.freq[i]-fmin)*s.nchan/(s.samp_rate*1e-6);
+    j0=(int) floor(y-w);
+    j1=(int) floor(y+w);
+
+    // Keep in range
+    if (j0<0)
+      j0=0;
+    if (j1>=s.nchan)
+      j1=s.nchan;
+    
+    // Find maximum and significance
+    zm=0.0;
+    jmax=0;
+    s1=0.0;
+    s2=0.0;
+    sn=0;
+    for (j=j0;j<j1;j++) {
+      z=s.z[i+s.nsub*j];
+      s1+=z;
+      s2+=z*z;
+      sn++;
+      if (z>zm) {
+	zm=z;
+	jmax=j;
+	}
+    }
+    za=s1/(float) sn;
+    zs=sqrt(s2/(float) sn-za*za);
+    sigma=(zm-za)/zs;
+
+    // Store
+    if (sigma>5.0 && s.mjd[i]>1.0) {
+      f=s.freq-0.5*s.samp_rate+(double) jmax*s.samp_rate/(double) s.nchan;
+      fprintf(file,"%lf %lf %f %d\n",s.mjd[i],f,sigma,site_id);
+      cpgpt1((float) i,(float) jmax,17);
+    }
+  }
+
+  // Close file
+  fclose(file);
+
+  return t;
+}
+
 
 void filter(struct spectrogram s,int site_id)
 {
@@ -82,7 +151,7 @@ void filter(struct spectrogram s,int site_id)
       else
 	mask[j]=0;
     }    
-
+    /*
     // Find maximum when points are adjacent
     for (j=0;j<s.nchan-1;j++) {
       if (mask[j]==1 && mask[j+1]==1) {
@@ -96,7 +165,7 @@ void filter(struct spectrogram s,int site_id)
 	  mask[j]=0;
       }
     }
-
+    */
     // Mark points
     for (j=0;j<s.nchan;j++) {
       if (mask[j]==1) {
@@ -123,9 +192,9 @@ int main(int argc,char *argv[])
   float cool_g[]={0.0,0.0,0.0,1.0,1.0,1.0,0.6,0.0,1.0};
   float cool_b[]={0.0,0.3,0.8,1.0,0.3,0.0,0.0,0.0,1.0};
   float xmin,xmax,ymin,ymax,zmin,zmax=8.0;
-  int i,j,k,flag=0,isel=0;
+  int i,j,k,flag=0,isel=0,sn;
   int redraw=1,mode=0,posn=0,click=0;
-  float dt,zzmax,s1,s2;
+  float dt,zzmax,s1,s2,z,za,sigma,zs,zm;
   int ix=0,iy=0,isub=0;
   int i0,j0,i1,j1,jmax;
   float width=1500;
@@ -294,7 +363,7 @@ int main(int argc,char *argv[])
 	cpgsci(7);
 	// Plot points
 	for (i=0;i<sel.n;i++) 
-	  cpgpt1(sel.x[i],sel.y[i],17);
+	  cpgpt1(sel.x[i],sel.y[i],4);
 	// Plot upper bound
 	for (i=0;i<sel.n;i++) {
 	  if (i==0)
@@ -323,6 +392,14 @@ int main(int argc,char *argv[])
     if (c=='q')
       break;
 
+    // Track
+    if (c=='t') {
+      for (i=0;i<nsat;i++) {
+	printf("Locating trace for object %05d\n",t[i].satno);
+	locate_trace(s,t[i],4171);
+      }
+    }
+
     // Select start
     if (c=='s') {
       sel.x[isel]=x;
@@ -338,7 +415,7 @@ int main(int argc,char *argv[])
 
     // Fit
     if (c=='f') {
-      tf=locate_trace(s,sel,site_id);
+      tf=fit_trace(s,sel,site_id);
       tf.site=site_id;
       continue;
     }
@@ -468,16 +545,28 @@ int main(int argc,char *argv[])
       for (i=i0;i<i1;i++) {
 	zzmax=0.0;
 	jmax=0;
+	s1=0.0;
+	s2=0.0;
+	sn=0;
 	for (j=j0;j<j1;j++) {
-	  if (s.z[i+s.nsub*j]>zzmax) {
-	    zzmax=s.z[i+s.nsub*j];
+	  z=s.z[i+s.nsub*j];
+	  if (z>zzmax) {
+	    zzmax=z;
 	    jmax=j;
 	  }
+	  s1+=z;
+	  s2+=z*z;
+	  sn++;
 	}
+	za=s1/(float) sn;
+	zs=sqrt(s2/(float) sn-za*za);
+	sigma=(zzmax-za)/zs;
+
 	f=s.freq-0.5*s.samp_rate+(double) jmax*s.samp_rate/(double) s.nchan;
-	if (s.mjd[i]>1.0)
+	if (sigma>5.0 && s.mjd[i]>1.0) {
 	  fprintf(file,"%lf %lf %f %d\n",s.mjd[i],f,zzmax,site_id);
-	cpgpt1((float) i,(float) jmax,17);
+	  cpgpt1((float) i,(float) jmax,17);
+	}
       }
       fclose(file);
     }
@@ -822,8 +911,8 @@ void plot_traces(struct trace *t,int nsat)
   return;
 }
 
-// Locate trace
-struct trace locate_trace(struct spectrogram s,struct select sel,int site_id)
+// Fit trace
+struct trace fit_trace(struct spectrogram s,struct select sel,int site_id)
 {
   int i,j,k,l,sn;
   int i0,i1,j0,j1,jmax;
@@ -895,3 +984,4 @@ struct trace locate_trace(struct spectrogram s,struct select sel,int site_id)
 
   return t;
 }
+
diff --git a/rftrace.c b/rftrace.c
index 0ef3e90..546849d 100644
--- a/rftrace.c
+++ b/rftrace.c
@@ -192,7 +192,7 @@ void identify_trace(char *tlefile,struct trace t,int satno)
     // Initialize
     imode=init_sgdp4(&orb);
     if (imode==SGDP4_ERROR)
-      printf("Error\n");
+      printf("SGDP4 Error\n");
 
     // Loop over points
     for (i=0,sum1=0.0,sum2=0.0;i<t.n;i++) {
@@ -350,6 +350,7 @@ struct trace *compute_trace(char *tlefile,double *mjd,int n,int site_id,float fr
     t[j].satno=satno;
     t[j].site=site_id;
     t[j].n=m;
+    t[j].freq0=freq0;
     t[j].mjd=(double *) malloc(sizeof(double)*m);
     t[j].freq=(double *) malloc(sizeof(double)*m);
     t[j].za=(float *) malloc(sizeof(float)*m);
diff --git a/rftrace.h b/rftrace.h
index d03b990..61e594e 100644
--- a/rftrace.h
+++ b/rftrace.h
@@ -1,7 +1,7 @@
 struct trace {
   int satno,n,site;
   double *mjd;
-  double *freq;
+  double *freq,freq0;
   float *za;
 };
 struct trace *compute_trace(char *tlefile,double *mjd,int n,int site_id,float fmin,float fmax,int *nsat);