Notes for building "next generation" converter

Left side is female DB25 (RS232), right side is Male DB25 (ALDL). The board is now sandwiched between the pins of the solder cups on these DB25's. Before you solder these cups to the board, make sure the printed circuit board with DB25's fits inside the black housing without a problem. If the board is too long, it will interfere with the lip that hangs down on the black shell. A little sanding with modest sandpaper (150-220 grit) laid on a table will make short work of any adjustments.

Note that capacitor legs have moved inboard from other picture. The polarity is the same, I just moved the traces closer to the MAXIM chip. NOTE: There is ONE capacitor that is 1uF at 50 volts. This is to be used on the power input. It is the second capacitor from the top.

Note the two diodes at the top middle of the board. Their stripe side is sticking in the air, with the legs wrapped down feeding the input pin of the 7805 voltage regulator. These diodes provide the port power option.

Note the diode on the upper right side of the board. This diode is if you want to bring cigarette lighter power in to the board. If you have trouble with the port power, you might try cig lighter power. The DB25 pin to connect the WHITE lead of the cigarette lighter adapter to would be pin 25. The RED lead would be connected to pin 21 (ground).

Note to the right-middle of the MAXIM chip, two diodes with their stripe sides sticking in the air. These are for filtering out noise.

All the transistors are laid out in the same positions as the previous version of the board.

Any questions? Email me! amattei@mindspring.com