It may need a resistor to ground something that draws 5-10ma. Some GPS rcvrs need the dc load to believe a antenna is attached.
On Fri, May 20, 2011 at 7:21 AM, Robert Watzlavick <roc...@watzlavick.com>wrote: > > > On 05/19/2011 10:35 PM, WB6BNQ wrote: > >> Robert, >> >> Two questions. >> >> First, what is the voltage at the 9390 antenna connector with nothing >> attached >> besides your DVM ? >> >> It shows 5V open circuit. > > > Second, what happens if you just attach the antenna straight to the 9390 ? >> By >> this i mean if voltage is on the antenna connector and while you are >> observing it >> and then attach the antenna what happens ? >> >> I found something interesting here - with it connected straight to the > antenna, I measured 4.6V. I connected and disconnected it several times and > didn't see any drops. But, after the 5th connection or so, I finally got > the 9390 to show the same behavior as with the splitter and shut off its > antenna supply. So it seems it's not exclusive to the splitter but just > that it occurs more often. The antenna is connected directly to the little > GPS daughterboard module and I don't have schematics for it. > > This isn't a showstopper, just interesting behavior. One of the things I > like about the 58536A is that it will continue to power the antenna if you > remove other receivers from the ports (for troubleshooting etc.) I guess > with this particular receiver, it is a little more sensitive to antenna > disconnects while it is powered on. > > I suspect there is some protection process with the 9390 and the load or >> reverse >> voltage present from the splitter is causing it to activate. However, I >> am not >> familiar with that unit. Just asking general troubleshooting questions. >> >> Bill....WB6BNQ >> >> Agree - thanks. > > > -Bob > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.