Subject: 9600 FULLDUPLEX on the Pac-Comm TNC-220 by D. Hulatt G4WFQ 19th Aug 90 ------------------------------ Locate 74HC4020 and remove from IC socket CAREFULLY bend pins 1 and 12 up Solder flying leads to pins 1 and 12 on 74HC4020 Solder flying lead to pin 12 on SIO 8530 chip Use a SPDT switch to switch to 2 signals from 4020 to SIO Replace 4020 Drill 1/4 inch hole in rear plate above RS232 slot Insert switch and secure. Thats it. Throw switch for 9600 FULLDUPLEX operation, revert for normal. NB: You still have to change buad rate in s/w. I hope this information will be of use to some. I would like to thank Uk Agent for trying to get info from Pac-Comm. It must be like trying to get blood out of a stone. Thanks Pac-Comm, no need to bother now I've done it myself! 73 de Dave G4WFQ @ GB7PET AUK.2404 19 Aug 90