subroutine ft8b_2(dd0,newdat,nQSOProgress,nfqso,nftx,ndepth,lapon,lapcqonly,   &
     napwid,lsubtract,nagain,iaptype,mycall12,mygrid6,hiscall12,bcontest,    &
     sync0,f1,xdt,xbase,apsym,nharderrors,dmin,nbadcrc,ipass,iera,msg37,xsnr)  

  use crc
  use timer_module, only: timer
  include 'ft8_params.f90'
  parameter(NP2=2812)
  character*37 msg37
  character message*22,msgsent*22
  character*12 mycall12,hiscall12
  character*6 mycall6,mygrid6,hiscall6,c1,c2
  character*87 cbits
  logical bcontest
  real a(5)
  real s1(0:7,ND),s2(0:7,NN),s1sort(8*ND)
  real ps(0:7),psl(0:7)
  real bmeta(3*ND),bmetb(3*ND),bmetap(3*ND)
  real llr(3*ND),llra(3*ND),llrb(3*ND),llrd(3*ND)           !Soft symbols
  real dd0(15*12000)
  integer*1 decoded(91),decoded0(91),apmask(3*ND),cw(3*ND)
  integer*1 msgbits(91)
  integer apsym(91)
  integer mcq(28),mde(28),mrrr(16),m73(16),mrr73(16)
  integer itone(NN)
  integer indxs1(8*ND)
  integer icos7(0:6),ip(1)
  integer nappasses(0:5)  !Number of decoding passes to use for each QSO state
  integer naptypes(0:5,4) ! (nQSOProgress, decoding pass)  maximum of 4 passes for now
  integer*1, target:: i1hiscall(12)
  complex cd0(3200)
  complex ctwk(32)
  complex csymb(32)
  logical first,newdat,lsubtract,lapon,lapcqonly,nagain
  equivalence (s1,s1sort)
  data icos7/3,1,4,0,6,5,2/  ! Flipped w.r.t. original FT8 sync array
  data mcq/1,1,1,1,1,0,1,0,0,0,0,0,1,0,0,0,0,0,1,1,0,0,0,1,1,0,0,1/
  data mrrr/0,1,1,1,1,1,1,0,1,1,0,0,1,1,1,1/
  data m73/0,1,1,1,1,1,1,0,1,1,0,1,0,0,0,0/
  data mde/1,1,1,1,1,1,1,1,0,1,1,0,0,1,0,0,0,0,0,1,1,1,0,1,0,0,0,1/
  data mrr73/0,0,0,0,0,0,1,0,0,0,0,1,0,1,0,1/
  data first/.true./
  save nappasses,naptypes

! All of the AP-related code in this routine needs to be re-written! AP decoding 
! passes are disabled for now.
!
  if(first) then
     mcq=2*mcq-1
     mde=2*mde-1
     mrrr=2*mrrr-1
     m73=2*m73-1
     mrr73=2*mrr73-1
     nappasses(0)=2
     nappasses(1)=2
     nappasses(2)=2
     nappasses(3)=4
     nappasses(4)=4
     nappasses(5)=3

! iaptype
!------------------------
!   1        CQ     ???    ???
!   2        MyCall ???    ???
!   3        MyCall DxCall ???
!   4        MyCall DxCall RRR
!   5        MyCall DxCall 73
!   6        MyCall DxCall RR73
!   7        ???    DxCall ???

     naptypes(0,1:4)=(/1,2,0,0/)
     naptypes(1,1:4)=(/2,3,0,0/)
     naptypes(2,1:4)=(/2,3,0,0/)
     naptypes(3,1:4)=(/3,4,5,6/)
     naptypes(4,1:4)=(/3,4,5,6/)
     naptypes(5,1:4)=(/3,1,2,0/)  
     first=.false.
  endif

  max_iterations=30
  nharderrors=-1
  fs2=12000.0/NDOWN
  dt2=1.0/fs2
  twopi=8.0*atan(1.0)
  delfbest=0.
  ibest=0

  call timer('ft8_down',0)
  call ft8_downsample(dd0,newdat,f1,cd0)   !Mix f1 to baseband and downsample
  call timer('ft8_down',1)

  i0=nint((xdt+0.5)*fs2)                   !Initial guess for start of signal
  smax=0.0
  do idt=i0-8,i0+8                         !Search over +/- one quarter symbol
     call sync8d(cd0,idt,ctwk,0,2,sync)
     if(sync.gt.smax) then
        smax=sync
        ibest=idt
     endif
  enddo
  xdt2=ibest*dt2                           !Improved estimate for DT

! Now peak up in frequency
  i0=nint(xdt2*fs2)
  smax=0.0
  do ifr=-5,5                              !Search over +/- 2.5 Hz
    delf=ifr*0.5
    dphi=twopi*delf*dt2
    phi=0.0
    do i=1,32
      ctwk(i)=cmplx(cos(phi),sin(phi))
      phi=mod(phi+dphi,twopi)
    enddo
   call sync8d(cd0,i0,ctwk,1,2,sync)
    if( sync .gt. smax ) then
      smax=sync
      delfbest=delf
    endif
  enddo
  a=0.0
  a(1)=-delfbest
  call twkfreq1(cd0,NP2,fs2,a,cd0)
  xdt=xdt2
  f1=f1+delfbest                           !Improved estimate of DF

  call sync8d(cd0,i0,ctwk,2,2,sync)

  j=0
  do k=1,NN
    i1=ibest+(k-1)*32
    csymb=cmplx(0.0,0.0)
    if( i1.ge.1 .and. i1+31 .le. NP2 ) csymb=cd0(i1:i1+31)
    call four2a(csymb,32,1,-1,1)
    s2(0:7,k)=abs(csymb(1:8))/1e3
  enddo  

! sync quality check
  is1=0
  is2=0
  is3=0
  do k=1,7
    ip=maxloc(s2(:,k))
    if(icos7(k-1).eq.(ip(1)-1)) is1=is1+1
    ip=maxloc(s2(:,k+36))
    if(icos7(k-1).eq.(ip(1)-1)) is2=is2+1
    ip=maxloc(s2(:,k+72))
    if(icos7(k-1).eq.(ip(1)-1)) is3=is3+1
  enddo
! hard sync sum - max is 21
  nsync=is1+is2+is3
  if(nsync .le. 6) then ! bail out
    nbadcrc=1
    return
  endif

  j=0
  do k=1,NN
     if(k.le.7) cycle
     if(k.ge.37 .and. k.le.43) cycle
     if(k.gt.72) cycle
     j=j+1
     s1(0:7,j)=s2(0:7,k)
  enddo  

  call indexx(s1sort,8*ND,indxs1)
  xmeds1=s1sort(indxs1(nint(0.5*8*ND)))
  s1=s1/xmeds1

  do j=1,ND
     i4=3*j-2
     i2=3*j-1
     i1=3*j
! Max amplitude
     ps=s1(0:7,j)
! For Gray bit-to-symbol mapping
     r1=max(ps(1),ps(2),ps(5),ps(6))-max(ps(0),ps(3),ps(4),ps(7))
     r2=max(ps(2),ps(3),ps(4),ps(5))-max(ps(0),ps(1),ps(6),ps(7))
     r4=max(ps(4),ps(5),ps(6),ps(7))-max(ps(0),ps(1),ps(2),ps(3))
     bmeta(i4)=r4
     bmeta(i2)=r2
     bmeta(i1)=r1
! Max log metric
     psl=log(ps+1e-32)
! Gray bit-to-symbol mapping
     r1=max(psl(1),psl(2),psl(5),psl(6))-max(psl(0),psl(3),psl(4),ps(7))
     r2=max(psl(2),psl(3),psl(4),psl(5))-max(psl(0),psl(1),psl(6),ps(7))
     r4=max(psl(4),psl(5),psl(6),psl(7))-max(psl(0),psl(1),psl(2),ps(3))
     bmetb(i4)=r4
     bmetb(i2)=r2
     bmetb(i1)=r1
  enddo

  call normalizebmet(bmeta,3*ND)
  call normalizebmet(bmetb,3*ND)
  bmetap=bmeta

  scalefac=2.83
  llra=scalefac*bmeta
  llrb=scalefac*bmetb
  apmag=scalefac*(maxval(abs(bmetap))*1.01)

! pass #
!------------------------------
!   1        regular decoding
!   2        erase 24
!   3        erase 48
!   4        ap pass 1
!   5        ap pass 2
!   6        ap pass 3
!   7        ap pass 4, etc.

  if(lapon) then 
     if(.not.lapcqonly) then
        npasses=4+nappasses(nQSOProgress)
     else
        npasses=5 
     endif
  else
     npasses=4
  endif

  do ipass=1,npasses 
!  do ipass=1,2 
     llrd=llra
     if(ipass.eq.2) llrd=llrb
     if(ipass.eq.3) llrd(1:24)=0. 
     if(ipass.eq.4) llrd(1:48)=0. 
     if(ipass.le.4) then
        apmask=0
        iaptype=0
     endif
        
     if(ipass .gt. 4) then
        if(.not.lapcqonly) then
           iaptype=naptypes(nQSOProgress,ipass-4)
        else
           iaptype=1
        endif
        if(iaptype.ge.3 .and. (abs(f1-nfqso).gt.napwid .and. abs(f1-nftx).gt.napwid) ) cycle 
        if(iaptype.eq.1 .or. iaptype.eq.2 ) then ! AP,???,??? 
           apmask=0
           apmask(1:27)=1    ! first 27 bits (9 tones) are AP
           if(iaptype.eq.1) llrd(1:27)=apmag*mcq(1:27)
           if(iaptype.eq.2) llrd(1:27)=apmag*apsym(1:27)
        endif
        if(iaptype.eq.3) then   ! mycall, dxcall, ???
           apmask=0
           apmask(1:54)=1   
           llrd(1:54)=apmag*apsym(1:54)
        endif
        if(iaptype.eq.4 .or. iaptype.eq.5 .or. iaptype.eq.6) then  
           apmask=0
           apmask(1:72)=1   ! mycall, hiscall, RRR|73|RR73
           llrd(1:56)=apmag*apsym(1:56)
           if(iaptype.eq.4) llrd(57:72)=apmag*mrrr 
           if(iaptype.eq.5) llrd(57:72)=apmag*m73 
           if(iaptype.eq.6) llrd(57:72)=apmag*mrr73 
        endif
        if(iaptype.eq.7) then   ! ???, dxcall, ???
           apmask=0
           apmask(31:54)=1  ! hiscall
           llrd(31:54)=apmag*apsym(31:54)
        endif
     endif

     cw=0
     call timer('bpd174_91 ',0)
     call bpdecode174_91(llrd,apmask,max_iterations,decoded,cw,nharderrors,  &
          niterations)
     call timer('bpd174_91 ',1)
     dmin=0.0
     if(ndepth.eq.3 .and. nharderrors.lt.0) then
        ndeep=3
        if(abs(nfqso-f1).le.napwid .or. abs(nftx-f1).le.napwid) then
          if((ipass.eq.3 .or. ipass.eq.4) .and. .not.nagain) then
            ndeep=3 
          else   
            ndeep=4  
          endif
        endif
        if(nagain) ndeep=5
        call timer('osd174_91 ',0)
        call osd174_91(llrd,apmask,ndeep,decoded,cw,nharderrors,dmin)
        call timer('osd174_91 ',1)
     endif
     nbadcrc=1
     message='                      '
     xsnr=-99.0
     if(count(cw.eq.0).eq.174) cycle           !Reject the all-zero codeword
     if(nharderrors.ge.0 .and. nharderrors+dmin.lt.60.0 .and. &        
        .not.(sync.lt.2.0 .and. nharderrors.gt.35)      .and. &
        .not.(ipass.gt.2 .and. nharderrors.gt.39)       .and. &
        .not.(ipass.eq.4 .and. nharderrors.gt.30)             &
       ) then
        call chkcrc14a(decoded,nbadcrc)
     else
        nharderrors=-1
        cycle 
     endif
     i5bit=16*decoded(73) + 8*decoded(74) + 4*decoded(75) + 2*decoded(76) + decoded(77)
     iFreeText=decoded(57)
     if(nbadcrc.eq.0) then
        decoded0=decoded
        if(i5bit.eq.1) decoded(57:)=0
        call extractmessage174_91(decoded,message,ncrcflag)
        decoded=decoded0
! This needs fixing for messages with i5bit=1:        
        call genft8_174_91(message,mygrid6,bcontest,i5bit,msgsent,msgbits,itone)
        if(lsubtract) call subtractft8(dd0,itone,f1,xdt2)
        xsig=0.0
        xnoi=0.0
        do i=1,79
           xsig=xsig+s2(itone(i),i)**2
           ios=mod(itone(i)+4,7)
           xnoi=xnoi+s2(ios,i)**2
        enddo
        xsnr=0.001
        if(xnoi.gt.0 .and. xnoi.lt.xsig) xsnr=xsig/xnoi-1.0
        xsnr=10.0*log10(xsnr)-27.0
        xsnr2=db(xsig/xbase - 1.0) - 32.0
        if(.not.nagain) xsnr=xsnr2
        if(xsnr .lt. -24.0) xsnr=-24.0
        
        if(i5bit.eq.1) then
           do i=1,12
              i1hiscall(i)=ichar(hiscall12(i:i))
           enddo
           icrc10=crc10(c_loc(i1hiscall),12)
           write(cbits,1001) decoded
1001       format(87i1)
           read(cbits,1002) ncrc10,nrpt
1002       format(56x,b10,b6)
           irpt=nrpt-30
           i1=index(message,' ')
           i2=index(message(i1+1:),' ') + i1
           c1=message(1:i1)//'   '
           c2=message(i1+1:i2)//'   '

           if(ncrc10.eq.icrc10) msg37=c1//' RR73; '//c2//' <'//      &
                trim(hiscall12)//'>    '
           if(ncrc10.ne.icrc10) msg37=c1//' RR73; '//c2//' <...>    '
           
!           msg37=c1//' RR73; '//c2//' <...>    '
           write(msg37(35:37),1010) irpt
1010       format(i3.2)
           if(msg37(35:35).ne.'-') msg37(35:35)='+'
           
           iz=len(trim(msg37))
           do iter=1,10                           !Collapse multiple blanks
              ib2=index(msg37(1:iz),'  ')
              if(ib2.lt.1) exit
              msg37=msg37(1:ib2)//msg37(ib2+2:)
              iz=iz-1
           enddo
        else
           msg37=message//'               '
        endif
        return
     endif
  enddo
  return
end subroutine ft8b_2

! This currently resides in ft8b_1.f90
!subroutine normalizebmet(bmet,n)
!  real bmet(n)
!
!  bmetav=sum(bmet)/real(n)
!  bmet2av=sum(bmet*bmet)/real(n)
!  var=bmet2av-bmetav*bmetav
!  if( var .gt. 0.0 ) then
!     bmetsig=sqrt(var)
!  else
!     bmetsig=sqrt(bmet2av)
!  endif
!  bmet=bmet/bmetsig
!  return
!end subroutine normalizebmet