[time-nuts] Serial-Ethernet

I just thought I'd report about a serial to Ethernet interface I just bought. I got one of these: http://www.amazon.com/gp/product/B00ATV2DX2 At the moment it is hooked up to my Z3801A and I am using Z38XX.exe from across the network. Using the included software and driver, I have the RS232 port

[time-nuts] Z3801A holdover

I just took a look at my Z3801A that has been in holdover for some time. I have been too busy to do anything about it until now. Before looking at the receiver stats just now, my first guess was that the Oncore GPS board went bad. However, I see that it is currently tracking 4 sats. I also see

[time-nuts] Racal Option 04E OCXO

I have many pictures and complete schematics of the Racal 04E optional OCXO used in many Racal counters. Ask if interested. -- Best wishes, Larry McDavid W6FUB Anaheim, California (SE of Los Angeles, near Disneyland) ___ time-nuts mailing list --

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

On Wed, Feb 24, 2016 at 2:53 PM, Nick Sayer via time-nuts < time-nuts@febo.com> wrote: > I can measure 1 ppb, but it takes 1000 seconds to do it ... My > understanding is that better GPSDOs are able to provide for more granular > phase detection. It doesn't take a lot of hardware to get about

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

Hi WWVB DSO’s were a pretty common thing back in the 70’s and 80’s. You could hold fractions of a ppm with them. With manual intervention / scheduling you could get into the “couple ppb” range on a good week. Comparative numbers would be 1x10^-11 on a GPSDO. All the same qualifiers about

[time-nuts] A few more FEI FE-405B oscillators available

Hello time-nuts, I have a few more of the characterized Frequency Electronics, Inc. FE-405B oscillators available. These units have ADEV plots by Corby Dawson from 1 to over 1000 seconds. All the units have had the temperature compensation disabled (but it is easy to reverse if desired, though

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

Hi The tick is a burst of audio at a fairly low frequency. You are going to need pretty good conditions to get 0.1 ms. The fade process over much of the day will spread that out a *lot*. Bob > On Feb 24, 2016, at 5:11 PM, Tim Shoppa wrote: > > Hal - > In my experience

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

Hi If you are looking at pool service, the first question would be how you connect to the backbone. If you are running something asymmetric (DSL / cable modem) you already have enough of an offset that it alone it far bigger than any other error in your system. Even with fancier

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

Hal - In my experience over more than a decade, the ntpd WWV audio refclock has jitter circa 0.1ms. This is not nanosecond-time-nut PPS territory. But it is more than good enough for WAN ntpd. I use a Ten-Tec RX-320 as a cheap frequency-agile receiver for WWV. In between 5MHz/10MHz/15MHz

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

> From what others on the list have said before, WWVB offers performance > that's at least a couple orders of magnitude worse than GPS, even if you > correct for all of the expected diurnal variations in LF propagation. Given > that a fairly pedestrian GPS module offers a nominal PPS accuracy of

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

> On Feb 24, 2016, at 8:30 AM, Chris Albertson > wrote: > > On Wed, Feb 24, 2016 at 6:22 AM, Neil Green wrote: > >> >> What would be my next step up be, hardware-wise, in terms of improving >> precision, stability, etc? A GPSDO? Budget is

Re: [time-nuts] Introduction

Dear Enrico, On 02/24/2016 06:55 AM, Enrico Bellotti wrote: Hello to all, first of all, thank you for the great and useful work that the time-nuts have done over the years. Welcome! I have finally been able to gather all my counters (HP5335A, HP51131A, HP5370A, HP5370B #1, HP5370B #2) and

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

What would be my next step up be, hardware-wise, in terms of improving precision, stability, etc? A GPSDO? Budget is limited as far as these things go - about £150 UK/$210 US. I have Symmetricom TS2100 with OCXO and GPS upgrades as primary server, accessible only at local network. It has

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

tsho...@gmail.com said: > My opinion if you want to serve reliable time through a longer GPS outage: > add a WWV or WWVB based radio clock. e.g. a shortwave radio and https:// > www.eecis.udel.edu/~mills/ntp/html/drivers/driver36.html Do you have any graphs comparing WWV or WWVB to GPS when

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

nc...@hotmail.co.uk said: > What would be my next step up be, hardware-wise, in terms of improving > precision, stability, etc? A GPSDO? Budget is limited as far as these things > go - about £150 UK/$210 US. How good is your antenna? How often does your current GPS setup run out of

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

On Wed, Feb 24, 2016 at 6:22 AM, Neil Green wrote: > > What would be my next step up be, hardware-wise, in terms of improving > precision, stability, etc? A GPSDO? Budget is limited as far as these things > go - about £150 UK/$210 US. Given that you already have the GPS

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

GPSDO's are very nice if you want a bench source for calibration purposes. On the subject of NTP servers... GPSDO's would be relevant when doing holdover through a GPS outage measured in days. My opinion if you want to serve reliable time through a longer GPS outage: add a WWV or WWVB based

Re: [time-nuts] Introduction

I've found with my HP5370B's they perform best over a fairly narrow range of input signal levels.(1 to 2 volts If I recall correctly ?) Some experiments might be in order for yours. Virtually all my testing was done with 5 or 10 MHz sine waves so this may or may not be helpful in your

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

On Wed, Feb 24, 2016 at 3:22 PM, Neil Green wrote: > I currently operate a stratum 1 NTP server in the NTP pool using a U-Blox > Max-7Q GPS module with PPS attached to, variously, a Raspberry Pi via GPIO or > a Celeron mini PC via serial DB-9. The machine does nothing but

Re: [time-nuts] Next step up from basic GPS/PPS timekeeping

I currently operate a stratum 1 NTP server in the NTP pool using a U-Blox Max-7Q GPS module with PPS attached to, variously, a Raspberry Pi via GPIO or a Celeron mini PC via serial DB-9. The machine does nothing but serve time to the pool. Operating systems of choice are Debian or FreeBSD.

[time-nuts] Next step up from basic GPS/PPS timekeeping

I currently operate a stratum 1 NTP server in the NTP pool using a U-Blox Max-7Q GPS module with PPS attached to, variously, a Raspberry Pi via GPIO or a Celeron mini PC via serial DB-9. The machine does nothing but serve time to the pool. Operating systems of choice are Debian or FreeBSD.

Re: [time-nuts] Introduction

On Wednesday, February 24, 2016 12:55:42 AM Enrico Bellotti wrote: > Hello to all, > > first of all, thank you for the great and useful work that the time-nuts > have done over the years. > > I have finally been able to gather all my counters (HP5335A, HP51131A, > HP5370A, HP5370B #1, HP5370B