Hi all, Still have problems, decoding Acars with my 486SX/33 Mhz. when i run the LoweAirmaster for Dos software on my Pentium II/300 Mhz i get less misdecode's and larger logfile's. Running the on 486 pure dos, no windows. Are the comm ports the problem?? has anyone a same experience?? All helps appreciated Regards Erik ---