Hi Scott, Many controllers have pullup resistors on their COR inputs so that they can be driven from open collector or relay contact COR outputs. With that arrangement, if the controller is configured for active high and the COR line is disconnected, the controller will think the receiver is active.
The best arrangement is the one that works for you. There aren't any standards -- except perhaps in industrial control, where there are fewer active low circuits due to the possibility of activating a circuit due to a pinched wire. 73, Bob Bob Schmid, WA9FBO, Member S-COM, LLC PO Box 1546 LaPorte, CO 80535-1546 970-416-6505 phone 970-419-3222 fax www.scomcontrollers.com -----Original Message----- From: scott w <kq...@yahoo.com> To: Repeater-Builder@yahoogroups.com Sent: Thu, Jun 3, 2010 2:55 am Subject: [Repeater-Builder] active low COR Hello to group, What is the advantage of an active low COR. Most I have talked to say they have their controllers set that way, so I set mine that way,plus the Maxtrac I am using as a receiver default is active low. I simulated a power failure to the reciever and the line went low and the transmitter thought it was time to transmit. I also accidently pulled the cord from the controller off the back of the receiver and again a low status and the transmitter thought it was time to transmit. Im not seeing a benefit of a active low COR in those repects. Should I go to active high or since those things dont usually happen often leave it LOW.. Any advice or ideas appreciated.. 73s
