[time-nuts] Re: GPS Control Loop

2022-04-27 Thread ASSI
On Dienstag, 26. April 2022 23:20:34 CEST Lux, Jim wrote: > That's the MCXO - uses third harmonic and fundamental to measure the > temperature. Q-Tech sells them. Or, more properly, has them in their > catalog and may be happy to quote a price and delivery. The datasheet > revisions are >5 years

[time-nuts] Re: GPS Control Loop

2022-04-26 Thread ASSI
On Montag, 25. April 2022 18:27:01 CEST André Balsa wrote: > A PDF of Shera's article can be found here (many thanks to whomever is > hosting this file): > > https://www.qsl.net/n9zia/wireless/QST_GPS.pdf > > To me, there is no doubt Shera's original design inspired all the following > DIY GPSDO

[time-nuts] Re: +1/f of transistors

2022-04-10 Thread ASSI
On Samstag, 9. April 2022 13:38:58 CEST use...@teply.info wrote: > IF the base and emitter doping would be done through ion implantation, > this can create a lot of defects, which act as recombination centres. …as does any other doping technique. The details of what defects are where and

[time-nuts] Re: +1/f of transistors

2022-04-10 Thread ASSI
On Samstag, 9. April 2022 18:29:11 CEST Lux, Jim wrote: > On 4/9/22 6:31 AM, Richard (Rick) Karlquist wrote: > > I am seeing a lot of unsupported "theories" about what should be done > > to make devices with low 1/f noise. It might be instructive for everyone > > to read Marv Keshner's PhD

[time-nuts] Re: 10 MHz TCXO periodically jumping 20 mHz up and down

2022-02-20 Thread ASSI
On Freitag, 18. Februar 2022 22:52:27 CET Attila Kinali wrote: > Quick side note: On modern, cheap TCXO systems, expecially those > for RTCs, frequency control is being done by a bank of switched > capacitors. This is mostly because capacitors can be implemented > in a standard digital CMOS

[time-nuts] Re: RTC DS3231: how well can it be regulated?

2021-07-18 Thread ASSI
On Sonntag, 18. Juli 2021 04:06:56 CEST Tim S wrote: > I did want to pose the question, are you aware of the existence > of DS1341/DS1342 RTCs? These parts have a 1pps (or power-line 50/60Hzr > following built-in. On these chips the PPS alignment is done by selecting an edge from a 128Hz

Re: [time-nuts] Raspberry Pi 4 oscillator replacement

2021-02-04 Thread ASSI
Avamander wrote: > I was wondering if anyone here has replaced the 54 MHz oscillator on the > Raspberry Pi 4 with a GNSS-disciplined rubidium standard? The same things as replacing the XTAL on an RPi 1…3 I'd guess. So, you need to remove the XTAL (hot air rework station), figure out which pin

Re: [time-nuts] NTP Servers - RPi, NTP-Sec, Teensy 4.1, and one on the way from eBay

2021-01-11 Thread ASSI
Am Sonntag, 10. Januar 2021, 23:07:02 CET schrieb Ben Hall: > pi@spy-pi:~ $ ntpq -p > remote refid st t when poll reach delay offset jitter >== >*192.168.4.66.PPS.1 u 94 1024 377

Re: [time-nuts] NTP Servers - RPi, NTP-Sec, Teensy 4.1, and one on the way from eBay

2021-01-10 Thread ASSI
Am Sonntag, 10. Januar 2021, 17:30:52 CET schrieb Ben Hall: > While on the NTP-Sec server, on the output of ntpq, there are at least four: > > delay offset jitter > == > 0. 0.0740 0.0027 > 85.4951 -1.7276 11.7616 > 40.9579 -1.9249 13.8848 > 25.7753 -0.5499

Re: [time-nuts] Ebay Huawei Ublox M8T Modules Warning

2021-01-10 Thread ASSI
Am Samstag, 9. Januar 2021, 23:38:35 CET schrieb gandal...@aol.com: > Now a question, supposing someone did follow that diagram and applied 5 > Volts to Vcc on the M8T, what is the risk of damage and would it be > immediately obvious? The commonly agreed upon definition of an abs max rating is

Re: [time-nuts] Raspberry Pi NTP server

2020-07-08 Thread ASSI
On Dienstag, 7. Juli 2020 18:27:01 CEST Petr Titěra wrote: > Timing on USB need not to be so horrible. Below is stats from my server > with GPS connected using FT232H chip (supporting high speed transfers on > USB). Yes, the jitter is far greater than on other computer where PPS is > connected

Re: [time-nuts] PPS stats

2020-07-08 Thread ASSI
On Montag, 6. Juli 2020 18:04:33 CEST Keith E. Brandt, WD9GET wrote: > Why isn't the kerninfo showing any info on the pps frequency, stability, > and jitter? Kernel support for PPS and for in-kernel PLL utilizing one PPS input are two different things, at least in the Linux kernel. You are

Re: [time-nuts] Vaperware Parts and pulse stretching circuits

2020-04-25 Thread ASSI
On Samstag, 25. April 2020 16:24:35 CEST John Moran, Scawby Design wrote: > As a few others have pointed out on this thread, there are some simple > methods of soldering fine-pitch devices. I use the one already mentioned > that can be done with a clunky soldering iron, some solder-wick and a low

Re: [time-nuts] NTP server using an OCXO, GPS chip and Raspberry Pi

2020-04-25 Thread ASSI
On Freitag, 24. April 2020 20:46:25 CEST Andreas Kempe wrote: > I want to build an affordable quality time source for my computer > club. I've been toying with the idea of using an oven controlled > oscillator from Ebay for getting a reasonable (0,5 ppm frequency > stability) 1 PPS signal and a

Re: [time-nuts] A look inside the DS3231

2020-04-19 Thread ASSI
On Sonntag, 19. April 2020 16:04:39 CEST Graham / KE9H wrote: > The RV-3028 is 3.2x1.5 mm in size, 1.5ppm, additionally trimmable, 45 nA > standby current, under $3 USD in price and in stock at Mouser and Digikey. > Of particular interest to me, besides all the normal features, this one > also

Re: [time-nuts] A look inside the DS3231

2020-04-19 Thread ASSI
[blast from the past…] Attila Kinali writes: > My guess would be that it's a PN-junction or a bandgap temperature > sensor somewhere on the chip. Adding another part increases the cost > of production quite considerably. The die micrograph shows one clearly identifiable classical 8:1 bandgap

Re: [time-nuts] The 10811 double oven mystery

2020-04-09 Thread ASSI
On Donnerstag, 9. April 2020 03:58:11 CEST Hal Murray wrote: > What's the problem with digital gear at cold temperatures? The only one I > can think of is that electrolytic capacitors stop working when the > electrolyte freezes. The two most common problems are that gates switch too fast so

Re: [time-nuts] weird Raspberry PPS+GPS NTP server behaviour

2020-03-03 Thread ASSI
[sorry for breaking the threading, I'm replying from the list archive since gmane.io does not have this list anymore] Hi David, [ntpheat] > I didn't know about that program and I'd like to try it here. A neat idea. > Is it available stand-alone - ready to run? I could compile it here given >

[time-nuts] time-nuts no longer carried by GMane.io

2020-03-03 Thread ASSI
Hi John, It seems that the time-nuts mailing list has lapsed from gmane.io (if indeed it got re-subscribed under the new domain, changed from formerly gmane.org) somewhere in January (there is one later mail from February, but I think that's courtesy of a cross-posting). Could you check