---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Fri 01/02/09: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:00 AM - Tripacer update (Bob Gibfried) 2. 10:41 AM - GPS Serial Data to Garmin GTX-327 Transponder (Matt Dralle) 3. 12:44 PM - Re: GPS Serial Data to Garmin GTX-327 Transponder (teamgrumman@aol.com) 4. 01:23 PM - Re: GPS Serial Data to Garmin GTX-327 Transponder (Doug McNutt) ________________________________ Message 1 _____________________________________ Time: 06:00:06 AM PST US From: "Bob Gibfried" Subject: Avionics-List: Tripacer update Two schools of thought. Some owners like everything original and there are a lot of shops rebuilding and restoring some of the original parts. My personal Tripacer is being updated as well as I can without resorting to all of the time and 337s necessary for a major conversion. New carter stack panel, 60 amp alternator, led cabin lights, KMD 150 GPS, etc. Would be interested in your updates. Bob, Wichita ________________________________ Message 2 _____________________________________ Time: 10:41:07 AM PST US From: Matt Dralle Subject: Avionics-List: GPS Serial Data to Garmin GTX-327 Transponder Listers, I've tried sending two different sources of NEMA 0183 data at 4800/9600/19200/38400/57600 baud rates to my Garmin GTX-327 on both serial input ports 1 (db25 Pin 2) and port 2 (db25 pin 19), and configured for "GPS" input. But I don't get anything on the 327 serial input test display. I have been successful at getting AirData Z-format from the GRT EFIS at 9600 baud into either of the GTX-327 serial ports, so the ports are good. The GTX-327 just won't seem to see the GPS data for some reason. Am I doing something wrong? Has anyone else tried this successfully? Thanks! Matt Dralle RV-8 #82880 N998RV ________________________________ Message 3 _____________________________________ Time: 12:44:31 PM PST US Subject: Re: Avionics-List: GPS Serial Data to Garmin GTX-327 Transponder From: teamgrumman@aol.com Call Jeff at (661) 949-8300 -----Original Message----- From: Matt Dralle Sent: Fri, 2 Jan 2009 10:39 am Subject: Avionics-List: GPS Serial Data to Garmin GTX-327 Transponder Listers, I've tried sending two different sources of NEMA 0183 data at 4800/9600/19200/38400/57600 baud rates to my Garmin GTX-327 on both serial input ports 1 (db25 Pin 2) and port 2 (db25 pin 19), and configured for "GPS" input. But I don't get anything on the 327 serial input test display. I have been successful at getting AirData Z-format from the GRT EFIS at 9600 baud into either of the GTX-327 serial ports, so the ports are good. The GTX-327 just won't seem to see the GPS data for some reason. Am I doing something wrong? Has anyone else tried this successfully? Thanks! Matt Dralle RV-8 #82880 N998RV ________________________________ Message 4 _____________________________________ Time: 01:23:20 PM PST US From: Doug McNutt Subject: Re: Avionics-List: GPS Serial Data to Garmin GTX-327 Transponder At 10:39 -0800 1/2/09, Matt Dralle wrote: >I've tried sending two different sources of NEMA 0183 data at >4800/9600/19200/38400/57600 baud rates to my Garmin GTX-327 on both >serial input ports 1 (db25 Pin 2) and port 2 (db25 pin 19), and >configured for "GPS" input. But I don't get anything on the 327 >serial input test display. I have been successful at getting >AirData Z-format from the GRT EFIS at 9600 baud into either of the >GTX-327 serial ports, so the ports are good. The GTX-327 just won't >seem to see the GPS data for some reason. > >Am I doing something wrong? Has anyone else tried this successfully? I recently had experience with a Garmin 425 GPS (a tiny one not really for aircraft use) that claimed to put out RS232 compliant signals. What I discovered, with an oscilloscope, was a signal level that was "low" at about +150 mV and high at about +4.5 V with a fairly high internal resistance that had problems at 1 mA output levels. Without careful grounding at the pins of the GPS the +150 mV was even worse. RS232-C, which is the only official RS232 spec I can afford right now calls for a negative going level for the low value and Garmin simply does NOT meet that. There are some newer RS232 specifications around that might describe Garmin's output level but when I asked all I got was "RTFM" and the PDF manual simply says RS232 compliant. I placed a 1.5 volt dry cell in series with Garmin's output with a polarity that subtracted 1.5 volts from all signals. The resulting data stream went negative and was acceptable to the old Macintosh I was working with at the time. Some USB to RS232 converters would work and others would not. You seem to be talking about the Garmin as a receiver rather than a transmitter and I have no idea how well Garmin's "RS232 compliant" receiver behaves. I do doubt that you will get an authoritative answer from them. -- --> A fair tax is one that you pay but I don't <-- ------------------------------------------------------------------------------------- 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.