It can be done through IO but unless you have some objection running the fan at half speed (or so) all the time is a much easier way to do it. If you are using muffin style fans you can put a resistor in series to accomplish that. For 12V fans a 30-100 ohm 1/2W resistor works good. Usually only a small amount of air across a heatsink is required for cooling so you can experiment with the proper speed. You could even use PTT to change the speed when you TX if you desire. I have not found that to be necessary. If you can find surplus 24V fans they run great on 12V without a resistor. 73 Doug WA3DSP http://www.crompton.com/hamradio Date: Sun, 3 Aug 2014 10:06:40 -0600 From: electricity440@gmail.com To: app_rpt-users@ohnosec.org Subject: [App_rpt-users] Simple I/O interface Hi, I have some cooling fans. I would like to have the fans turn ON when the radio transmits, and stay on for sixty seconds after the radio stops transmitting and then turn off. I would like to use the I/O interface on my URIx. (The I/O will then trigger a Solid State Relay ,and then turn on the Fans) How can I do this with the software? Can I write it with Scripts? What commands would I need to detect if it is sending a PTT, detect PTT off, wait time, turn the output to high, turn the output to low, always "look" for a TX, etc. Example code is always really nice for a beginner like me :-) 73 SkylerKDØWHB -- Skyler Fennell amsatnet.infoKDØWHBelectricity440@gmail.com _______________________________________________ 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.