As a remainder, how to make an FMS PPM to PC serial cable. For USB, add a serial to USB converter cable.
Based on a PIC 12F675. Ok for 98, ME, 2K, XP, portables.
[î]needs a TTL compatible PPM signal ( (*) and ref to doc), which is the case of most transmitters[/i]

Schema: http://www.jdm-nivelles.be/fichiers/...cteurs_PCM.pdf

PIC hex file: http://www.jdm-nivelles.be/fichiers/fms/pcmcab.hex

Printed Circuit:http://www.jdm-nivelles.be/fichiers/...it_imprime.jpg

"Manual" printed circuit: http://www.jdm-nivelles.be/fichiers/...uit_manuel.jpg

Tools to help you:
Virtual scope on PC audio input (mike) (to find your PPM signal): http://polly.phys.msu.su/~zeld/oscill.html

COM signal analyser: http://www.jdm-nivelles.be/fichiers/...32analyser.exe

PPM signal analyser (has COMx and audio interface inputs): http://www.jdm-nivelles.be/fichiers/fms/Analyser31.exe

Transmitters info (how to find your PPM signal or make a buddy cable): http://users.belgacom.net/TX2TX

All docs and other softwares (viewing plane or helico, record a flight, ...):
http://www.jdm-nivelles.be/fichiers/fms/SPCMliste.htm

Philippe
Brussels Belgium
JDM- Nivelles

(*): TTL signal: low < 0.8V, high > 2.4V. Check with scope.
Edit: remark from a user on the FMS forum (http://cgi.ethz.ch/~mmoeller/fms => Forum: it is in English ): one could use a lower voltage zener (3.3v?) , still be in the PIC specs at 4MHz, and achieve a lower "high" voltage. NOT TESTED !