Jamey, The cm108 has a weak pullup and you must use a diode pointed out from the FOB to the radio COS. The radio side of the diode can pull it low. Since the diode blocks any positive voltage from going back into the FOB the high does not matter as long as it is above a couple of volts. Make sure the low is really low on that radio. Also make sure the diode is good. You really should use a Schottky diode but you can get away with a good switching diode. With carrierfrom=usb you should be able to short the COS to ground and then briefly unground it and ground it again and see a hungup message in the client - 'asterisk -rvvv' - at the Linux prompt. 73 Doug WA3DSP http://www.crompton.com/hamradio From: Jamey.Wright@morgan911.org To: app_rpt-users@ohnosec.org Date: Sun, 26 Jul 2015 22:36:50 +0000 Subject: [App_rpt-users] CM108 Fob Interfaces I am using modified CM108 sound fobs on my system. I also use simpleusb and do not do DSP carrier detect. One of them has COR that is active low and it works no problem. The other one , the radio COR is only active high. The active high is 5V. In the simpleusb.conf I have it set for carrierfrom=usb but it doesn't work. Does the active COR voltage need to be more than 5V? Thanks Jamey WR4JW _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users To unsubscribe from this list please visit http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users and scroll down to the bottom of the page. Enter your email address and press the "Unsubscribe or edit options button" You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.