MPX Europa problems

[daviruz]

Hi.
I've made a parallel ppm-cable for my Multiplex Europa transmitter according to the schematic under "Manual" (there is one listed specifically for this transmitter). But since i didn't have any zensers at home i used two 2.3V LED's instead, giving me about 4.6V, which i have verified with my oscilloscope. This shouln't introduce any problems, since LED's generally have better characteristics then zeners. Anyway, on to the problem.
I have only got this cable to work in FMS 2.0 B5, on an old P120 laptop with win98se, with very poor results. Very laggy response, and very much ripple. Completely unusable.
On other machines it won't work at all. 2.0 B5 says "Kein Signal", and i don't get any response in any version. I have tried setting the parallel port in a lot of different settings (ECP, EPP, EPP1.7 EPP1.9, EPPECP etc) changing both IO address and IRQ, but nothing seems to work. The IRQ's i have tried has not been shared.
Does anyone know what might be causing this?

Jocke.

[kris_geusens]

The interface only works on win9x, not on XP or 2K.

[daviruz]

Yeah, i know. I forgot to mention that i have only tested it in win98se.

I just tried the PPjoy interface that someone here wrote, wont work there either. It just stops at "Waiting for transmitter signal".

[daviruz]

Solved it!
I added a 1n4148 in series with the two LED's (2.1V + 2.1V + 0.8V = 5.0V), works great now.