

I guess 100k, connecting pins 1-3 (1x), 1-6 (1y), 9-11 (2x), and 9-13 (2y).

Or: Get an 8-bit DA-Converter (merely a couple of transistors and
Resistors) and an OpAmp to compare its output to the voltage you want to
measure, connect them to a spared printer port (if you have one), and do
the rest by software (stepwise refinement). The port addresses for your
printer ports are probably: &H378 (LPT1), &H278 (LPT2). This should work
well enough for your purposes.

Hope this helps

--
GMD,  Schloss Birlinghoven,  Postfach 1316,  D-5205 St. Augustin 1,  FRG