Re: [time-nuts] Fun with the Z3815
Have you tried commanding a survey to get the receive to ignore the old location? :PTIME:GPSYSTEM:POSITION:SURVEY ONCE John WA4WDL -- From: Morris Odell vilgo...@bigpond.net.au Sent: Saturday, August 11, 2012 7:27 AM To: time-nuts@febo.com Subject: [time-nuts] Fun with the Z3815 HI all, I posted a question recently here for a friend re a Z3815 not receiving, having formerly been perfect. Here's what he says now: I've done more testing with my HP3815A. Firstly I rewired the coax cable between the external antenna connector and the PCB - there was some evidence of snagging on the outside of the cable where it passes through the metal casing. However, no improvement in performance resulted. Also the blocking capacitor referred to turns out to be an inductor. DC is making it through to the antenna amp, and there is continuity along the whole route from N-connector to the Furuno GPS receiver input. The status screen on Hyperterminal shows that something is happening, however. The SYNCHRONIZATION section on the display showed outputs invalid, TFOM = 9 and FFOM = 3 (i.e. no sync). But the ACQUISITION section showed that although no satellites had been tracked, several had been detected - in fact 9 of them. Also, the correct date and time were displayed. The LAT and LONG data was incorrect, being the original northern hemisphere figures. Health monitor reads OK and there are no ALARMS. So the receiver appears to be picking up enough information to show the satellites' PRN, EL and AZ (and furthermore they change between readings) as well as the date and time. What's more the time displayed is local time! Any suggestions as to what's going on? Morris ___ 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] Fun with the Z3815
Try to preset the receiver too: :SYSTEM:PRESET But first you can read the system log to try to identify when the failure started: :DIAGNOSTIC:LOG:READ:ALL? Doing a SYSTEM:PRESET will clear the log, of course. Very strange the inductor on the antenna cable: my Z3815A has a capacitor also because there is a different power for the antenna and I suspect that you have a short between the Furuno antenna power and the Z3815A antenna power. On Sat, Aug 11, 2012 at 1:51 PM, jmfranke jmfra...@cox.net wrote: Have you tried commanding a survey to get the receive to ignore the old location? :PTIME:GPSYSTEM:POSITION:SURVEY ONCE John WA4WDL -- From: Morris Odell vilgo...@bigpond.net.au Sent: Saturday, August 11, 2012 7:27 AM To: time-nuts@febo.com Subject: [time-nuts] Fun with the Z3815 HI all, I posted a question recently here for a friend re a Z3815 not receiving, having formerly been perfect. Here's what he says now: I've done more testing with my HP3815A. Firstly I rewired the coax cable between the external antenna connector and the PCB - there was some evidence of snagging on the outside of the cable where it passes through the metal casing. However, no improvement in performance resulted. Also the blocking capacitor referred to turns out to be an inductor. DC is making it through to the antenna amp, and there is continuity along the whole route from N-connector to the Furuno GPS receiver input. The status screen on Hyperterminal shows that something is happening, however. The SYNCHRONIZATION section on the display showed outputs invalid, TFOM = 9 and FFOM = 3 (i.e. no sync). But the ACQUISITION section showed that although no satellites had been tracked, several had been detected - in fact 9 of them. Also, the correct date and time were displayed. The LAT and LONG data was incorrect, being the original northern hemisphere figures. Health monitor reads OK and there are no ALARMS. So the receiver appears to be picking up enough information to show the satellites' PRN, EL and AZ (and furthermore they change between readings) as well as the date and time. What's more the time displayed is local time! Any suggestions as to what's going on? Morris ___ 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] Fun with the Z3815
Hi As I recall, this was a 3815 that was working and then stopped working. If it's back to it's original location, then the new location from the survey was never saved to eprom. Once he gets a new survey, make sure to save it. If it's not saved, the unit will revert to the old location every time the power is cycled. Bob On Aug 11, 2012, at 7:27 AM, Morris Odell vilgo...@bigpond.net.au wrote: HI all, I posted a question recently here for a friend re a Z3815 not receiving, having formerly been perfect. Here's what he says now: I've done more testing with my HP3815A. Firstly I rewired the coax cable between the external antenna connector and the PCB - there was some evidence of snagging on the outside of the cable where it passes through the metal casing. However, no improvement in performance resulted. Also the blocking capacitor referred to turns out to be an inductor. DC is making it through to the antenna amp, and there is continuity along the whole route from N-connector to the Furuno GPS receiver input. The status screen on Hyperterminal shows that something is happening, however. The SYNCHRONIZATION section on the display showed outputs invalid, TFOM = 9 and FFOM = 3 (i.e. no sync). But the ACQUISITION section showed that although no satellites had been tracked, several had been detected - in fact 9 of them. Also, the correct date and time were displayed. The LAT and LONG data was incorrect, being the original northern hemisphere figures. Health monitor reads OK and there are no ALARMS. So the receiver appears to be picking up enough information to show the satellites' PRN, EL and AZ (and furthermore they change between readings) as well as the date and time. What's more the time displayed is local time! Any suggestions as to what's going on? Morris ___ 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] Fun with the Z3815
On 8/11/12 4:16 AM, Azelio Boriani wrote: Very strange the inductor on the antenna cable: my Z3815A has a capacitor also because there is a different power for the antenna and I suspect that you have a short between the Furuno antenna power and the Z3815A antenna power. Think you looking at different things. There should be an inductor at the DC injection point, connecting to the signal line. And a cap as a DC block twards the receiver in-line with it. ___ 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] Fun with the Z3815
Of course, but they say that there is a DC continuity from the N connector downto the Furuno receiver: this is very strange. These the exact words: DC is making it through to the antenna amp, and there is continuity along the whole route from N-connector to the Furuno GPS receiver input. Very strange also because the inductor will prevent the receiver from getting any signal. Another strange thing: I haven't never saved any survey in my Z3815A and I have seen that in case of a power cycle the survey is repeated. The faulty Z3815A seems always acquiring and never tracking: maybe a Furuno clock problem? What can prevent a GPS receiver to enter the tracking state? On Sat, Aug 11, 2012 at 10:03 PM, Christopher Brown cbr...@woods.netwrote: On 8/11/12 4:16 AM, Azelio Boriani wrote: Very strange the inductor on the antenna cable: my Z3815A has a capacitor also because there is a different power for the antenna and I suspect that you have a short between the Furuno antenna power and the Z3815A antenna power. Think you looking at different things. There should be an inductor at the DC injection point, connecting to the signal line. And a cap as a DC block twards the receiver in-line with it. ___ 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.
