---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 06/21/08: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:36 PM - Millivolt Power Source? (r falstad) 2. 03:14 PM - Re: Millivolt Power Source? (jetboy) 3. 05:20 PM - NAV Troubleshooting (Jim Piavis) 4. 05:40 PM - Re: NAV Troubleshooting (Bruce Gray) 5. 05:50 PM - Re: NAV Troubleshooting (Ron Quillin) 6. 06:21 PM - Re: Diode Wiring (revenson@comcast.net (Roger Evenson)) 7. 07:12 PM - Re: NAV Troubleshooting (Jim Piavis) 8. 09:17 PM - Re: Re: NAV Troubleshooting (Ron Quillin) ________________________________ Message 1 _____________________________________ Time: 12:36:37 PM PST US From: "r falstad" Subject: AeroElectric-List: Millivolt Power Source? Is there a reasonably easy way to fabricate a millivolt source to calibrate an engine gauge? I need something in the range of 10 - 100 mVDC, say in increments of 10 mV. I've got a bunch of resistors. Can is just start linking them together and checking with my voltmeter until I get what I need? I presume that once I get the right voltage, I won't have to worry about blowing the instrument -- that it won't draw any more current than it is capable of handling. Correct? Thanks. Bob ________________________________ Message 2 _____________________________________ Time: 03:14:18 PM PST US Subject: AeroElectric-List: Re: Millivolt Power Source? From: "jetboy" Instrumentation people use a purpose made calibration source for this, what you suggest should be adequate for your task. May I suggest obtaining a 10-turn trimmer in the order of 100 ohms and feeding that from 12v via a resistor around 5K ohms. that will give you as fine an adjustment you will need with the digital voltmeter across the output (middle connection of the trimmer) No need to limit the output as the 5K resistor will do that. If you have other than a 100 or 200 ohm adjustable pot, just fit a 100 ohm resistor across it. Ralph -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=188952#188952 ________________________________ Message 3 _____________________________________ Time: 05:20:58 PM PST US From: Jim Piavis Subject: AeroElectric-List: NAV Troubleshooting I've recently started flying my RV-7 with a Garmin 480/ SL-30. NAV antenna is an Archer antenna in the right tip. Strobe/ nav light cables are run per Archer instructions along leading edge of the antenna. COM works great on both radios, but I'm getting nothing for NAV and need to troubleshoot the p roblem. The single coax hits a splitter, which feeds the 480 and SL-30. What's the best method for troubleshooting? Thanks, Jim RV-7 Redmond, WA ________________________________ Message 4 _____________________________________ Time: 05:40:29 PM PST US From: "Bruce Gray" Subject: RE: AeroElectric-List: NAV Troubleshooting If both nav radios are down, I'd suspect the splitter. Bruce www.Glasair.org -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jim Piavis Sent: Saturday, June 21, 2008 8:17 PM Subject: AeroElectric-List: NAV Troubleshooting I've recently started flying my RV-7 with a Garmin 480/ SL-30. NAV antenna is an Archer antenna in the right tip. Strobe/ nav light cables are run per Archer instructions along leading edge of the antenna. COM works great on both radios, but I'm getting nothing for NAV and need to troubleshoot the problem. The single coax hits a splitter, which feeds the 480 and SL-30. What's the best method for troubleshooting? Thanks, Jim RV-7 Redmond, WA ________________________________ Message 5 _____________________________________ Time: 05:50:44 PM PST US Subject: Re: AeroElectric-List: NAV Troubleshooting From: Ron Quillin At 17:16 6/21/2008, you wrote: >I've recently started flying my RV-7 with a Garmin 480/ SL-30. NAV >antenna is an Archer antenna in the right tip. Strobe/ nav light >cables are run per Archer instructions along leading edge of the >antenna. COM works great on both radios, but I'm getting nothing for >NAV and need to troubleshoot the problem. The single coax hits a >splitter, which feeds the 480 and SL-30. Both the 480 and SL30 use separate antennas for COM and NAV. Two COM antennae, correct? You say you're splitting an antenna. Just the NAV, right? Is NAV bad on both the 480 and the 30? How is GS? Ron Q. ________________________________ Message 6 _____________________________________ Time: 06:21:55 PM PST US From: revenson@comcast.net (Roger Evenson) Subject: AeroElectric-List: Re: Diode Wiring > >Just received the diode assembly from B&C for the main bus to endurance > >bus wiring. The wiring diagram that came with it shows two of its > >terminals joined going to the main bus. In the Aero Connection, Bob says > >only one of the terminals goes to the main bus and the other two can be > >removed. > > > >Please clarify--which is correct? > > Flip a coin . . . it doesn't matter much. > SOMETIMES . . . the two paralleled diodes > match close enough to sort-of share the > loads but It's poor practice to depend on > it. How big are your e-bus loads? > > Bob . . . E-BUS loads about 3.5 amps; maximum 9.5. Roger. ________________________________ Message 7 _____________________________________ Time: 07:12:54 PM PST US From: Jim Piavis Subject: AeroElectric-List: Re: NAV Troubleshooting Yes, separate COM antennas for both radios, and only the one NAV, and NAV i s bad on both. I can't get an identifier on either so I haven't checked GS either. I'm suspecting a bad BNC connector somewhere between the splitter and the a ntenna. Subject: Re: NAV Troubleshooting From: Ron Quillin (rjquillin@gmail.com) Date: Sat Jun 21 - 5:50 PM At 17:16 6/21/2008, you wrote: >I've recently started flying my RV-7 with a Garmin 480/ SL-30. NAV >antenna is an Archer antenna in the right tip. Strobe/ nav light >cables are run per Archer instructions along leading edge of the >antenna. COM works great on both radios, but I'm getting nothing for >NAV and need to troubleshoot the problem. The single coax hits a >splitter, which feeds the 480 and SL-30. Both the 480 and SL30 use separate antennas for COM and NAV. Two COM antennae, correct? You say you're splitting an antenna. Just the NAV, right? Is NAV bad on both the 480 and the 30? How is GS? Ron Q. ________________________________ Message 8 _____________________________________ Time: 09:17:09 PM PST US Subject: Re: AeroElectric-List: Re: NAV Troubleshooting From: Ron Quillin At 19:05 6/21/2008, you wrote: >Yes, separate COM antennas for both radios, and only the one NAV, >and NAV is bad on both. I can't get an identifier on either so I >haven't checked GS either. > > I'm suspecting a bad BNC connector somewhere between the splitter > and the antenna. I'd agree it's something between the splitter and the antenna. Connectors always a good place to start. Splitters; being the passive devices they are, not much to fail except perhaps the input connector. Don't forget both the 480 and 30 again split the NAV signal internally for VOR-LOC/GS, so a good signal to them is important. Ron Q. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-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/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-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.