SHORTWAVE CONVERTER Parts List C1 Optional capacitor. Use 150pF with 5 Mhz crystal, or 47pF with 8 Mhz If using crystal � 10 Mhz omit this capacitor. C2 33 pF C3,C5 220 pF C4 .047 �F D1 Zener diode between 5.1v - 6.2v (2N4691 or equivalent) R1 1K�, � watt resistor U1 NE602N Frequency Converter IC T1 10.7 Mhz miniature IF transformer (green core) XTAL 5 Mhz or 8 Mhz crystal, or other values (see text file XTAL.TXT) One for each band you like to listen to 8-pin DIP socket (for U1) J1,J2 RCA jacks [J2 is optional, see note 3 below] Motorola plug (optional. If installing converter externally, use for connecting cable to car radio's antenna jack). Radio Shack parts #274-711 14-pin wire-wrap socket and 14-pin DIP headers for mounting crystals Optional (see file XTAL.TXT) Hookup wire Schematic ========= ����������������������������/\/\/\� +12v � ����� � � R1 ���C3 ���Ŀ xtal � � ��� ����� � � � ����� � � J2 (to car radio antenna jack) � � � � ��Ŀ C5 ������������������������� � � o�������Ķ�������������������Ĵ 7 6 8� � ���� �5 � � �gnd � U1 � � � � � J1 (ant.) ���������Ŀ � NE602 � � � D1 ��Ŀ � 3����������Ĵ � ����Ĵ�������Ŀ � o�������Ĵ1 � � � Frequency � � � � ���� � T1 4��nc ���C1*� Converter � � � � � � ��� � � � � ��������Ĵ2 � � � � ��� � � � 5����������Ĵ � ��� C4 � � ����������� � 3 � � � � ������������������������� � � � � � � �������������������������������������������������������������������������� �gnd ----------------------------- Notes: 1) Virtually any construction method (point-to-point wiring, wire wrapping, etc.) should work, but a printed circuit board is recommended for both ease and neatness of construction. PC board construction would probably also help minimize undesirable RF interference from strong local broadcast stations. See file READ.ME for source of PC board. 2) Connect external antenna to J1 (it works with anything over 2', but better results are obtained with longer lengths. 3) J2 connects to car radio's antenna jack. If mounting the converter inside the car radio, omit J2 and run a wire directly from where the center connector of J2 is indicated to the car radio's antenna jack, otherwise use coax cable to connect from J2 to car radio antenna jack (see note 3). 4) It is strongly suggested that you install the converter inside the chassis of the car radio (it simplifies the wiring and reduces noise). If you do not have room to do so, use a metal case for the converter and a SHORT length of shielded coax cable for the connection from the converter to the car radio's antenna jack. 5) Connect +12 volt power input to car radio's on/off switch. That way you can turn both radio and converter on with that switch. 6) When everything is working, tune in a shortwave station near the middle of the dial and adjust the slug of T1 for the strongest signal. 7) You may use a signal generator or crystal oscillator to calibrate the dial, if desired.