Re: [time-nuts] 58536A splitter and 9390-6000 GPS
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. BillWB6BNQ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
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.comwrote: 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. BillWB6BNQ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
I thought the 58536A was supposed to provide a load to the other receivers for that reason. But now that I look at the datasheet more closely, that feature may only be available for the 58537. -Bon On May 20, 2011, at 7:25 AM, paul swed paulsw...@gmail.com wrote: 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.comwrote: 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. BillWB6BNQ 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. ___ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
I have a 58536A. Although it isn't mentioned in the datasheet or manual, mine has a DC load on each input. The load is four 1330 ohm surface mount resistors in parallel, e.g. 332 ohms or about 15 ma @ 5 volts. Ed Robert Watzlavick.com wrote: I thought the 58536A was supposed to provide a load to the other receivers for that reason. But now that I look at the datasheet more closely, that feature may only be available for the 58537. -Bon On May 20, 2011, at 7:25 AM, paul swed paulsw...@gmail.com wrote: 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.comwrote: 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. BillWB6BNQ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
As I mentioned earlier I would have guessed about 300 ohms at 5 V. Good luck On Fri, May 20, 2011 at 10:21 AM, Ed Palmer ed_pal...@sasktel.net wrote: I have a 58536A. Although it isn't mentioned in the datasheet or manual, mine has a DC load on each input. The load is four 1330 ohm surface mount resistors in parallel, e.g. 332 ohms or about 15 ma @ 5 volts. Ed Robert Watzlavick.com wrote: I thought the 58536A was supposed to provide a load to the other receivers for that reason. But now that I look at the datasheet more closely, that feature may only be available for the 58537. -Bon On May 20, 2011, at 7:25 AM, paul swed paulsw...@gmail.com wrote: 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.comwrote: 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. BillWB6BNQ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
Hi: It's pretty easy to connect an Ohm meter to the 58536 when it's not connected to anything else and measure the load resistance on the output ports. In a similar fashion you can connect different value resistors to the antenna terminals of the GPS receiver to see what values it likes. Some GPS receivers have not only antenna detection but in addition have short circuit detection, i.e. there is a min and max value of load resistor they are looking for. Have Fun, Brooke Clarke http://www.PRC68.com ___ 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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
So absolutely funny today and this thread. I now have 8 GPS rcvrs austrons, odetics, HP etc I just built a sleezy 1 X 8 splitter using Home depot 2.5 Ghz splitters. Have been doing this for years but with a 4 X. This issue exactly bit me. I put all the rcvrs online last night. One was acting goofy. Thought, well its old will have to troubleshoot it. Nope a 330 ohm to ground on a BNC T fixed it right up. Guess I should take my own suggestion some times. :-) Regards Paul WB8TSL On Fri, May 20, 2011 at 1:06 PM, Brooke Clarke bro...@pacific.net wrote: Hi: It's pretty easy to connect an Ohm meter to the 58536 when it's not connected to anything else and measure the load resistance on the output ports. In a similar fashion you can connect different value resistors to the antenna terminals of the GPS receiver to see what values it likes. Some GPS receivers have not only antenna detection but in addition have short circuit detection, i.e. there is a min and max value of load resistor they are looking for. Have Fun, Brooke Clarke http://www.PRC68.com ___ 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.
[time-nuts] 58536A splitter and 9390-6000 GPS
I received my Symmetricom 58536A GPS antenna splitter today (new from eBay) and did some testing with my Datum 9390-6000, Datum TS2100, and Thunderbolt. The Thunderbolt and TS2100 work fine with the splitter but the 9390 has some interesting behavior with the splitter. If the 9390 is connected by itself to the splitter, it doesn't report any satellites. However, if I then connect either of the other two receivers (Thunderbolt or TS2100) to the splitter, the 9390 will start picking up satellites. Then, if I disconnect the other receivers and leave the 9390 connected by itself, it continues to work. I tested this several times and it seems to be repeatable behavior. So as long as a different receiver has been connected to the splitter at least once, the 9390 works with it. I'm thinking the initial surge of connecting the 9390 to the splitter is causing a momentary overcurrent which shuts down the antenna supply. In the failure case, the voltage measured (with a T) at the splitter from the 9390 is 0V. In the working after a different receiver has been connected case, I measure 4.3V. The other two receivers output 5V with no load and about 4.6V under load connected to the splitter. Has anybody seen this before? The antenna is a Symmetricom AT575 type antenna. -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.
Re: [time-nuts] 58536A splitter and 9390-6000 GPS
Robert, Two questions. First, what is the voltage at the 9390 antenna connector with nothing attached besides your DVM ? 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 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. BillWB6BNQ Robert Watzlavick wrote: I received my Symmetricom 58536A GPS antenna splitter today (new from eBay) and did some testing with my Datum 9390-6000, Datum TS2100, and Thunderbolt. The Thunderbolt and TS2100 work fine with the splitter but the 9390 has some interesting behavior with the splitter. If the 9390 is connected by itself to the splitter, it doesn't report any satellites. However, if I then connect either of the other two receivers (Thunderbolt or TS2100) to the splitter, the 9390 will start picking up satellites. Then, if I disconnect the other receivers and leave the 9390 connected by itself, it continues to work. I tested this several times and it seems to be repeatable behavior. So as long as a different receiver has been connected to the splitter at least once, the 9390 works with it. I'm thinking the initial surge of connecting the 9390 to the splitter is causing a momentary overcurrent which shuts down the antenna supply. In the failure case, the voltage measured (with a T) at the splitter from the 9390 is 0V. In the working after a different receiver has been connected case, I measure 4.3V. The other two receivers output 5V with no load and about 4.6V under load connected to the splitter. Has anybody seen this before? The antenna is a Symmetricom AT575 type antenna. -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.
