---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Wed 01/02/08: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:38 PM - GPS antenna tripping breaker (Robin Hou) ________________________________ Message 1 _____________________________________ Time: 02:38:55 PM PST US From: Robin Hou Subject: Avionics-List: GPS antenna tripping breaker I run into a possible antenna related problem when testing my Northstar M3 GPS. First, let me describe my set up. My M3 is wired to MD40 CDI, Narco AR850, and an USB RS-485 converter to a PC. During my test, I connected a Trimble GPS antenna (P/N 16248-20) via an SMA-to-BNC adapter. I used the Trimble antenna because that was what I have on hand although I knew it is not an approved antenna for M3. My M3 did acquire GPS signals OK, and outputed GPS position to my PC. However, after few minutes, my ship power 3A breaker tripped. I felt the power wire and the breaker, and they are HOT. I re-wired my setup to a seprate 12V battery via a 5A fuse, and it again tripped the fuse. And the M3 felt very hot like a light bulb. I then tried a 10A fuse & it managed to run for 15 min without tripping the fuse. I know I should have measue the amp but did not because I don't have a amp meter that will handle the current. I let the M3 cooled then use new 3A fuses for the rest of my test. I found the M3 would run for more than 30 min without tripping the 3A fuse and not getting hot when the antenna was disconnected. I intend to buy an M3 compatible antenna for my install, but I want to confirm that the Trimble antenna, and not the M3, was the cause of hight current draw. Any idea of how can I confirm that short of sending my M3 to an avionice shop for a yellow tag? Thanks in advance. Robin Hou --------------------------------- Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message avionics-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Avionics-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/avionics-list Browse Digests http://www.matronics.com/digest/avionics-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.