Hello Said, Thanks for the detailed reply, it makes sense. But both unit , the HP and the FURY board running under the same software simultaneously / GPS Con / and I was mentioning the same small "windows" TI to GPS, and the FURY displays much better figures then HP.....but probably each units gives out / display / different data?????? Also the graphic display / BLUE / on the FURY board the max ampl between +2,2nsec and -2,0nsec sometimes +0,7nsec , -1,7nsec... the HP unit never goes under +15nsec and -20nsec...... almost 10 times worse..... Anyhow I am happy because it seems to me that the HP is still OK after 3 years of sleep.....
Rgsa Ernie. -----Original Message----- From: [EMAIL PROTECTED] To: [email protected] Sent: Thu, 13 Nov 2008 10:41 pm Subject: Re: [time-nuts] HP Z3801A Question Hello Ernie, as Bjoern mentioned I think the HP is indicating Time Interval between GPS and OCXO 1PPS in nanoseconds, while the Fury is indicating estimated frequency accuracy, a unitless number. The Fury is showing estimated average frequency error over the last 1000 seconds, similar to AVAR 1000s. You can run GPScon on Fury too, and should be able to compare against the graphic you did for the HP unit. Or you could set the LCD of the Fury to show Time Interval to UTC, or probe this time interval to UTC with the command ptim:tint? that will return the offset in nanoseconds as well. An offset of +/-50ns to UTC seems to be normal for the HP unit. On the Fury, I would expect this to be +/-10ns on a good OCXO. To the benefit of the Z3801A unit: if the HP unit indicates a larger offset, it may also be because it's internal GPS is not as good as the Fury GPSDO receiver. It does not necessarily mean the OCXO is causing the error, it could be that the HP GPS is causing the error, and the HP OCXO is still dead-on because it filters out its higher GPS errors. bye, Said In a message dated 11/13/2008 02:45:57 Pacific Standard Time, [EMAIL PROTECTED] writes: And running parallel the FURY board with a TEMEX OCXO and displays +1,6E-10 is the average very often 10E-11 and sometimes for a relative short time / 4-5 min / 1,4E-12. Any idea why the Z3801A not displaying better figure?? Something wrong with the HP unit???? Thanks Ernie. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
