I think your problem is still your cable.

You did not indicate that you tried it with the programmer plugged directly
into the PC's port.  When I tried to use mine with a ribbon cable, it
failed exactly as you described.  I fixed the problem by using a cable with
a metal shell not a plastic one which most ribbon cable connectors use
(contacts the chassis of the PC).  The shells on both ends of the cable
must be connected together for it to work.  This solution worked for mine
and a friend who had the same problem.  If you don't want to make a new
cable, try connecting the PC's chassis to the programmers ground and see if
it works.

Norm

At 10:39 AM 3/30/98 -0500, you wrote:
>
>Up to this point I have tried:
>
>1) Changing the programming wire (presently using
>   a 5 inch male/female D-type wire.
>2) Checking the output voltage at specific points
>      a)  Input voltage is 18-19V DAC
>      b)  TTL (7406)  = 5V
>      c)  Vin into LM317  18V+
>          Vout from LM317 regulator gives 13V (exactly as
>                                               specified)
>3) Also tried externally power the Vin for LM317, supplying 18V+ from two
>   9V dry cells.  Vout reads 13V (good!)
>4) Since the ITU program is DOS based, I have load the
>   programm in MS-DOS settings.
>5) Checked soldering job.
>