On 2/27/2012 8:48 PM, [email protected] wrote: > So, is the K3 serial port supposed to crap out when the rig's voltage > supply isn't optimum? >
Several questions. First, how are you powering the rig? Two wires straight to the battery? What conductor size? How long? Did you have two wires running to the battery, or were you using chassis as return? The latter is a recipe for disaster. How were you powering the computer? What was the "good antenna?" Was it a mobile antenna or an antenna rigged separately from the vehicle, like a dipole strung in trees? Thanks to paint between sections of the body, the chassis bonding in many cars ranges from awful to non-existent, and antennas attached to a car use the chassis as return for antenna current. This current can wreak havoc with any electronics in the vehicle. Even a ground-mounted vertical close to the vehicle can do that too. What was the serial cable? Was it twisted pair or parallel wires inside a shield? Parallel wires inside a shield are very subject to the strong magnetic fields produced by antenna current. Twisted pair provides FAR better immunity from RFI. See http://audiosystemsgroup.com/RFI-Ham.pdf for details of how to build a serial cable with far better RF immunity, and other advice on avoiding RFI problems in a mobile installation. There's also detail about that cable in http://audiosystemsgroup.com/HamInterfacing.pdf 73, Jim Brown K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
