Tuesday, April 20, 2010

RS-232 / Keyboard Interface Assembly

PS-2/RS232 to ASCII Keyboard Adapter Assembly
(designed by Mike Willegal)

I spent about an hour assembling the adapter PCB tonite. I took my time, otherwise I suppose you could build this board in about 30 minutes. I started off by cleaning the board with a tissue splashed with a bit of isopropyl alcohol. I soldered all of the jumper wires first, which took about 40 minutes. This was the most challenging part of assembly, the rest was a breeze. The only thing I have left to do is solder the ZIFF socket (when I receive it). Notice that I used a pair of needle nosed vice-grips to crimp the ribbon cable. This worked perfectly, I was amazed at how it snapped right into place!.


1. Use "helping hands" if you can. Otherwise, tape the PCB to your workbench so the PCB doesn't slide around on you.
2. After inserting the .1uF caps, GENTLY pull the leads through with a pair of small pliers.
3. Cut and strip all of your jumper wires beforehand. (See my previous post)
4. Use really thin solder (e.g. .020)
5. Use masking tape on EVERY component you solder including the jumper wires. The only exception is the RS-232 connector (DB-9), which easily snaps into place before soldering.
7. Check your connections with a magnifying glass and multi-meter (set to measure OHMs) to make sure there are no shorts between adjacent soldering points.
8. Solder a BARE wire between pins 16 and 5v. THEN solder a wire from pin 15 to the bare wire (Thus providing 5v to pin 15).

1 comment:

  1. I would recommend mounting the ribbon cable connector in a spare socket before attaching the ribbon cable. This will help prevent any bent or broken pins.