diff --git a/gcom2.f90 b/gcom2.f90
index bf340c110..7b13547df 100644
--- a/gcom2.f90
+++ b/gcom2.f90
@@ -50,6 +50,7 @@ integer ndebug         !Write debugging info?                   GUI
 integer ndphi          !Set to 1 to compute dphi             GUI,Decoder
 integer nhispol        !Pol angle matching HisCall or HisGrid Decoder
 integer nt1            !Time to start FFTs                      GUI
+integer nxant          !Antenna configuration: 0='+', 1='x'     GUI
 integer nblank         !Is NB checked?                          GUI
 integer nfmid          !Center frequency of main display        GUI
 integer nfrange        !Frequency range of main display         GUI
@@ -109,7 +110,7 @@ common/gcom2/fcenter,ps0(431),psavg(450),s2(64,3100),ccf(-5:540),           &
      ndecdone,lauto,mantx,nrestart,ntr,nmsg,nsave,nadd5,                    &
      dftolerance,LDecoded,rxdone,monitoring,nzap,minsigdb,                  &
      nclearave,nfreeze,nafc,ncsmin,newspec,nfa,nfb,nfcal,idphi,nkeep,       &
-     nmode,mode65,nbpp,ndebug,ndphi,nhispol,nt1,                            &
+     nmode,mode65,nbpp,ndebug,ndphi,nhispol,nt1,nxant,                      &
      nblank,nport,mousedf,mousefqso,neme,nrw26,naggressive,ntx2,nagain,     &
      shok,sendingsh,d2a(661500),d2b(661500),b(60000),jza,jzb,ntime,         &
      idinterval,msmax,lenappdir,idf,ndiskdat,nlines,nflat,ntxreq,ntxnow,    &
diff --git a/map65.py b/map65.py
index a63b5c3a7..82c72ba6b 100644
--- a/map65.py
+++ b/map65.py
@@ -1307,6 +1307,7 @@ def update():
     Audio.gcom2.neme=neme.get()
     Audio.gcom2.ndepth=ndepth.get()
     Audio.gcom2.multicast=multicast.get()
+    Audio.gcom2.nxant=options.xant.get()
     try:
         Audio.gcom2.idinterval=options.IDinterval.get()
     except:
@@ -1836,6 +1837,7 @@ try:
                 Audio.gcom2.nport=0
             Audio.gcom2.pttport=(options.PttPort.get()+'            ')[:12]
         elif key == 'Mileskm': options.mileskm.set(value)
+        elif key == 'Xant': options.xant.set(value)
         elif key == 'AudioOut':
             try:
                 g.ndevout.set(value)
@@ -1936,6 +1938,7 @@ f.write("HisGrid " + t + "\n")
 f.write("IDinterval " + str(options.IDinterval.get()) + "\n")
 f.write("PttPort " + str(options.PttPort.get()) + "\n")
 f.write("Mileskm " + str(options.mileskm.get()) + "\n")
+f.write("Xant " + str(options.xant.get()) + "\n")
 f.write("AudioOut " + options.DevoutName.get() + "\n")
 f.write("SamFacOut " + str(options.samfacout.get()) + "\n")
 if options.addpfx.get().lstrip()=="": options.addpfx.set("_")
diff --git a/map65a.F90 b/map65a.F90
index 43184f6cc..2cf1526e3 100644
--- a/map65a.F90
+++ b/map65a.F90
@@ -273,6 +273,10 @@ subroutine map65a(newdat)
               if(decoded(1:4).eq.'RO  ' .or. decoded(1:4).eq.'RRR  ' .or.  &
                  decoded(1:4).eq.'73  ') nsync2=nsync2-6
               nwrite=nwrite+1
+              if(nxant.ne.0) then
+                 npol=npol-45
+                 if(npol.lt.0) npol=npol+180
+              endif
               call cs_lock('map65aa')
               if(ndphi.eq.0) then
                  write(11,1010) nkHz,ndf,npol,nutc,dt,nsync2,decoded,nkv,nqual
@@ -367,6 +371,10 @@ subroutine map65a(newdat)
            nsync2=nint(10.0*log10(sync2)) - 40 !### empirical ###
            if(decoded(1:4).eq.'RO  ' .or. decoded(1:4).eq.'RRR  ' .or.  &
                 decoded(1:4).eq.'73  ') nsync2=nsync2-6
+           if(nxant.ne.0) then
+              npol=npol-45
+              if(npol.lt.0) npol=npol+180
+           endif
            call cs_lock('map65ac')
            write(26,1014) f0,ndf,ndf0,ndf1,ndf2,dt,npol,nsync1,       &
                 nsync2,nutc,decoded,nkv,nqual,nhist
diff --git a/options.py b/options.py
index 46b3ff407..46cd41ba1 100644
--- a/options.py
+++ b/options.py
@@ -86,6 +86,15 @@ rb5.pack(anchor=W,side=LEFT,padx=2,pady=2)
 rb6.pack(anchor=W,side=LEFT,padx=2,pady=2)
 f1.pack()
 
+f2=Frame(g1.interior(),width=100,height=20)
+xant=IntVar()
+Label(f2,text='Antennas:  ').pack(side=LEFT)
+rb7=Radiobutton(f2,text='+ ',value=0,variable=xant)
+rb8=Radiobutton(f2,text='x',value=1,variable=xant)
+rb7.pack(anchor=W,side=LEFT,padx=2,pady=2)
+rb8.pack(anchor=W,side=LEFT,padx=2,pady=2)
+f2.pack()
+
 #g3=Pmw.Group(root)
 g3=Pmw.Group(root,tag_text="Miscellaneous")
 temp_prefix=Pmw.EntryField(g3.interior(),labelpos=W,label_text='DXCC prefix:',