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Parts List

C1-C5             2.2 uf Tantalum                         R1-R2              3.3 K ohm

R3                    10 ohm                                     R4-R8              1 K ohm

J1                     DB9F-RA                                J2                     IDC Shrouded Header

U1                   MAX232 IC                             U2                   74HC00 or 74LS00 IC

LED                 Green or Red 3 mm                 

P1-P2              10 pin polarized IDC plug with strain relief

Cable               10 conductor ribbon cable (approximately 30 inches)

Assembly – Refer to PDF file for parts placement

 1.        Insert C1-C5 2.2 uf tantalum capacitors.  Observe polarity.  Solder, trim leads.

2.        Insert R1-R2 3.3 k ohm resisters (orange-orange-red-gold).  Solder, trim leads.

3.        Insert R3 10 ohm resister (brown-black-black-gold).  Solder, trim leads.

4.        Insert R4-R8 1 k ohm resisters (brown-black-red-gold).  Solder, trim leads.

5.        Insert DB9RA J1 connector.  Solder the mounting tabs first, making sure solder flows deep into holes, then solder pins. 

6.        Insert IDC shrouded header J2.  The cutout or “notch”  in the center is placed on the side of the board closest to where the IC’s will be placed and not on the side of the board where the edge is. Solder.

7.        Insert LED.  When viewing the LED from the bottom, the flat side should face the edge of the board.  Solder and trim.

8.        Insert IC’s.  Pin 1 on each IC will be located closest to the IDC shrouded header.  Solder. 

9.        Inspect the circuit board for proper parts placement and the bottom for solder shorts.  Flux may be removed using 91% rubbing alcohol or other flux removal chemicals and an old toothbrush.  Let dry thoroughly before connecting.  This completes construction of the board.

10.    Trim the ends of the ribbon cable so they are square. Remove the top strain relief from the IDC connector.  Insert the ribbon cable into the IDC connector so that the red striped wire enters the side with the arrow pointing upwards toward it.  Yes, this is backwards but the strain relief will reverse the direction the cable exits from the connector.   Apply pressure as evenly as possible across the IDC connector and press the connector together.  Drape the cable across the top and press the strain relief into place.  Repeat for other end.

11.    When connected to the radio and the radio is powered on, the LED should light.  Refer to troubleshooting if the board does not work.  

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