
        1200 Baud AFSK Modem fr Atari ST am RS232 Port
          Stromversorgung aus der RS232 Schnittstelle
            Treiber-Software L2STX (c) 1994 OE5DXL


RS232
Pin            ---------
     D1        !       !
 4 o--!>!--*---! 78L05 !----*--------+
     D2    !   !       !    !        !
20 o--!>!--*   ---------    !        !
           !       !   100nF!        !
     47uF ===      !       ===       !
     16V  ---      !        !        !
           !       !        !        !
 7 o--+   ---     ---      ---       !
      !                              !
      !                              !
     ---             ------------    !
                   8 !          !1   !            -------
 3 o-----------------! RxD   +5V!----*         +--! 10k !------o Nf
                     !          !10  !   100nF !  -------
     ------- D3    14!          !----*        ===     +-----+
 2 o-! 47k !--!>!-*--! TxD      !4   !         ! 100nF!     !
     -------      !  !       in !----+---------+     ===   ---
                  !16!          !11  !                !    ! !
  33pF +-----*----+--!       out!----+----------------+    ! !<--o Mic
      ===    !    !  !          !    *---------------+ 10k ! !
       !    ---   !  !          !   ---              !     ---
      ---  -----  !  !          !   ! !              !      !
  4.433619 !   !  !  !          !   ! !15k           !     ---
     MHz   -----  !  !   3105   !   ! !              !
            ---   !  !          !7  ---  -------     !
             !    !15!       lev!----*---! 18k !--+  !
             *----+--!          !2       -------  !  !
        33pF !    !  !          !----+           --- !
            ===   !  !          !5   !               !
             !    !  !          !----+               !
            ---   !  !       gnd!                    !
                  !  ------------                    !
                  !  13! 12!  9!                     !
                  !    !   !   !                     !
                  !   --- --- ---                    !
                  !                                  !
                  !    +---*--*---------------*------*
                  !    !   !  !              ---    ---
                  !  10! 16! 3!          180k! !330k! !  BC547 o..
                  !  ------------            ! !    ! !
         -------  ! 2!          !5   ------- ---    --- !------oPTT
      +--! 33k !--*--!          !----! 18k !--+------+--!
      !  -------     !          !    -------  !      !  !>--
     ---           13!          !15           !      !     !
                  +--!          !-------------*      !     !
                  !  !          !             !      !    ---
                  !11! 74HC123  !       100nF===     !
                  +--!          !14           !      !
                     !          !-------------+      !
                     !          !7                   !
                     !          !--------------------*
                     !          !        (100uF)47uF===  PTT-Watchdog-Zeit
 D1..D3 1N4148 o..  !          !6                  ---
                     !          !--------------------+
                     ------------
                      1!  8!  9!
                       !   !   !
                      --- --- ---

+ sind nur berkreuzungen oder Ecken
* sind Verbindungen
Viel Spa beim Lten

