anchor.diff:  // se nahodou nema nejake navestidlo pred cestou JC rozsvitit jinak.
   procedure TJCDb.UpdatePrevSignal(signal: TBlkSignal);
   var JC: TJC;
  -    prev_signal: TBlkSignal;
  +    prevSignal: TBlkSignal;
       code: TBlkSignalCode;
   begin
     for JC in Self.JCs do
  
positive.code:     if ((JC.data.nzv) and (code <> ncVolno)) then
        code := TBlkSignal.AddOpak(code);
  
      prev_signal.signal := code;
     end;
  end;
  
  
negative.code:         (JC.data.nextSignalType <> TJCNextSignalType.signal) or
          (JC.data.nextSignalId <> signal.id)) then continue;
  
      Blocks.GetBlkByID(JC.data.signalId, TBlk(prevSignal));
  
      if (not prevSignal.IsGoSignal()) then continue;
      if (prevSignal.changing) then continue;
  
      if ((signal.IsGoSignal()) and (not signal.IsOpakVystraha())) then
       begin
  