uses IdSNTP;

procedure TForm1.Button1Click(Sender: TObject);
begin
 with TidSNTP.Create(Self) do try
   Host:='clock.nc.fukuoka-u.ac.jp';//'time-nw.nist.gov';
   Port:=123;
   Self.Caption:=
   FormatDateTime('YY/MM/DD HH:MM:SS',DateTime);
  finally free;end;
end;