Re: [time-nuts] HP 5065A repair...

That's great. Another old HP box brought back to life. -pete On Sun, Jul 30, 2017 at 4:24 PM, paul swed wrote: > Ulf very good and great to hear. I did look at the clock motor driver and I > believe you can use a ttl flip flop to drive the two transistors just fine. > I

[time-nuts] A look inside the DS3231

Lower drain means a smaller battery or backup source... and in today's world of electronics smaller is better. But, past a certain point, it all boils down to a "spec waving" contest ;-) > What's the motivation for this, other than "because we can"? Aren't existing RTC

[time-nuts] HP 5065A repair...

After having salvaged an old 5065A that was decomissioned in 1987 due to Rubidium cavity heater short circuit, I have now, several weeks later eventually managed to what I think repair it. Using a GPS-Diciplined HP105A as oscilloscope trigger, the 5MHz O/P is absolutely still. "Continous

Re: [time-nuts] Interfacing of 74ALVC divider chain to ADF4350 output (yet another low jitter sine-to-logic thread ; ) )

Hello, Thank you for your reply! Monday, July 31, 2017, 0:25:19, Attila Kinali wrote: A> Alternatively, use something like an SY89874 as first divider A> stage to get down to a more managable frequency range, then A> continue with your ALVC dividers. I think it will be easier (faster and

Re: [time-nuts] Interfacing of 74ALVC divider chain to ADF4350 output (yet another low jitter sine-to-logic thread ; ) )

On Sun, 30 Jul 2017 23:52:50 +0300 Yuri Ostry wrote: > But interfacing of 74ALVC flip-flop input to a ADF output in a 160-260 MHz > range is not so easy question for me, especially taking low jitter > requirements into account. Maybe someone can share tested working solution >

[time-nuts] Interfacing of 74ALVC divider chain to ADF4350 output (yet another low jitter sine-to-logic thread ; ) )

Hello, Trying to make low-PN fine tuning step synth for experiments in HF range from the parts I have on hand. Looks like the best I can do is to add extra dividers to chinese ADF4350 board from eBay that was used in the past and now is collecting dust on the shelf. But interfacing of 74ALVC

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

The typical method of frequency correction is not to add or subtract capacitance across the crystal, (like an old analog engineer would do) but rather to add or subtract pulses to the stream of cycles/pulses coming out of the crystal oscillator. More the kind of correction a digital engineer would

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

On Sun, Jul 30, 2017, at 03:37 PM, Mark Sims wrote: > A friend of mine is an engineer for one of the biggest manufacturers of > clock chips and has worked quite a bit on their clock chips and is quite > familiar with the issues of building consistent ultra low power > oscillators in a production

[time-nuts] A look inside the DS3231

A friend of mine is an engineer for one of the biggest manufacturers of clock chips and has worked quite a bit on their clock chips and is quite familiar with the issues of building consistent ultra low power oscillators in a production product. Getting nanowatt (and now sub-nanowatt) level

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

On Sun, 30 Jul 2017 08:53:51 -0500 Didier Juges wrote: > I believe I have read an app note some time ago, it may have been from > Maxim describing a kind of ring oscillator being used as a temperature > sensor which drew much less power than a bandgap or a PN junction and >

Re: [time-nuts] Trimble Thunderbolt no longer determines the correct date

Unfortunately I did not have the log activated. Although I did not see a phase shift I think that that may be just luck as looking back at the screen print of tboltmon 1 sec after the roll, I see that the DAC voltage changed by +0,00533mV from the value 10mins prior to the roll. My antenna is

Re: [time-nuts] time-nuts Digest, Vol 156, Issue 30

Chris, I have one NTP GPS based server running locally but I wanted to also setup the Mac with the Thunderbolt as a second NTP server. This way instead of using an external NTP server as a backup I would have a second local server. The Mac is Unix based and has a built in NTP server but it is

Re: [time-nuts] Trimble Thunderbolt no longer determines the correct date

Hi Mike, > I was running Tboltmon as the rollover occurred and did not see any phase > shift. I'm pleased you saw no phase shift at all. Did you happen to have a TBoltmon log running? > Maybe your phase offset was due to your Tbolt being in survey mode and its > apparent position shifted .

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

That device also has analog circuitry for the oscillator itself and the temperature sensor and the temperature compensation. I believe I have read an app note some time ago, it may have been from Maxim describing a kind of ring oscillator being used as a temperature sensor which drew much less

[time-nuts] Low-power oscillators (was: A look inside the DS3231)

On Sun, 30 Jul 2017 08:15:57 -0400 Tim Shoppa wrote: > I would imagine there's a series of patents by watch > companies on this subject as well probably all back in the 1970's and There are also a lot of papers and books. I can recommend those written by Eric Vittoz, who

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

On the subject of low-current 32kHz oscillators: DS3231 spec says typical 1uA for timekeeping and circa 600uA for temperature conversion. I understand they periodicailly kick the temperature conversion on but only for extremely short duty cycles and this is included in the 1uA. Standard DS12887

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

On Sun, 30 Jul 2017 12:23:17 +0200 Pete Stephenson wrote: > > > - I find it remarkable that this circuit can operate on less than a > > > microamp during normal usage, including temperature conversion. > > > > That's not so remarkable. If you make the transistors long, then >

Re: [time-nuts] Thunderbolt rollover glitch

On Sun, Jul 30, 2017, at 04:49 AM, Mark Sims wrote: > It looks like it took three hours for the effects of the rollover glitch > to mostly settle out. > > BTW, if you only use Lady Heather with a Thunderbolt, you can force the > rollover state from the command line or heather.cfg file by using

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

On Sun, Jul 30, 2017, at 11:15 AM, Attila Kinali wrote: > On Sat, 29 Jul 2017 20:32:30 +0200 > Pete Stephenson wrote: > > > - There's several square grids of circles-in-squares circuit elements. I > > have no idea what these are. > > If you look closely, these are actually

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

On Sat, 29 Jul 2017 20:32:30 +0200 Pete Stephenson wrote: > - There's several square grids of circles-in-squares circuit elements. I > have no idea what these are. If you look closely, these are actually suqares-in-squares. I am not sure, but my guess would be that these are

Re: [time-nuts] Trimble Thunderbolt no longer determines the correct date

Hi, I was running Tboltmon as the rollover occurred and did not see any phase shift. Old type Tbolt firmware 3.0 Maybe your phase offset was due to your Tbolt being in survey mode and its apparent position shifted . Mike > Le 30 juil. 2017 à 02:16, Tom Van Baak a