On 3/31/19 5:29 PM, Neville Michie wrote:
I have a Philips quartz clock that runs on 4.19 MHz.
In spite of the high frequency it still runs for years
on a C cell.
Can any of the quartz crystal gurus explain why this
frequency was chosen? I believe that this clock was
supposed to have better than
Could it be that the actual crystal frequency is 4194204 Hz?
This is the 24th power of 2 (if my math is correct).
An easy way to get 1 pps.
Possibly a compromise between oscillator frequency and battery life.
Usually the higher the frequency, within reason, the easier it is to see
a frequency err
Some recent list comments have reminded me that I have an "over capacity" of
the Spirent GSS4100 GPS Simulator, don't yer just love that "over capacity"
psychobabble, you can almost feel the attached redundancy notices, and could
well do with shifting a couple.
A few years ago an Ebay UK scrap m
Hi
Simple answer is that it likely is an AT cut crystal. You can get a 1 ppm-ish
sort of stability over
0 to 50 C out of an AT. The 32 KHz crystal you sort of expect to see likely has
a couple hundred
ppm-ish stability over the same temperature range.
32 KHz crystal have been the norm in “qua
2 to the 22nd power is 4.194304MHz.
32768 Hz crystals are a tuning fork cut with a very different temperature
curve than a typical AT cut which your 4.19MHz crystal probably is.
Tim N3QE
On Sun, Mar 31, 2019 at 6:03 PM Neville Michie wrote:
> Hi,
> I have a Philips quartz clock that runs on 4.
I forgot to add that there's nothing remarkable about 4.194304 MHz in
terms of stability - it's just high enough to fit in reasonably small
packaging for clock use, and not take too-too much power. Lower
frequencies can work just fine, but the crystal tends to get way bigger.
The 32,768 kHz pie
Neville Michie wrote:
Hi,
I have a Philips quartz clock that runs on 4.19 MHz.
In spite of the high frequency it still runs for years
on a C cell.
Can any of the quartz crystal gurus explain why this
frequency was chosen? I believe that this clock was
supposed to have better than usual accuracy.
Your crystal doesn't show enough digits to see why it's a common value.
The "exact" number should be 4.194304 MHz, which is 2^22. It can be
divided by this base-2 integer conveniently to make 1 Hz for clock use.
The crystal marking, especially on small, common parts is often rounded
or truncate
Easy. 2^22 is 4194304. This means that a crystal of that frequency connected to
a chain of 22 flip-flops will produce one pulse per second. More modern Quartz
clocks are based on 32768Hz crystals which is 2^15Hz. The reason for the change
is that such low frequency crystals require a tuning-fork
In message , Neville Michie
writes:
>Can any of the quartz crystal gurus explain why this
>frequency was chosen?
2 to the 22nd power = 4194304 ?
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer | BSD since
Could it really be 4.194304 MHz (2^22 Hz)?
Dana
On Sun, Mar 31, 2019 at 5:03 PM Neville Michie wrote:
> Hi,
> I have a Philips quartz clock that runs on 4.19 MHz.
> In spite of the high frequency it still runs for years
> on a C cell.
> Can any of the quartz crystal gurus explain why this
>
The following wikipedia article:
https://en.wikipedia.org/wiki/Omega_Marine_Chronometer
mentions a "*Marine Chronometer clock using an advanced 4.19 MHz quartz
resonator giving an unparalleled accuracy of less than 5 seconds per year
under calibre 1525*." My guess is that this crystal technolo
Hi,
I have a Philips quartz clock that runs on 4.19 MHz.
In spite of the high frequency it still runs for years
on a C cell.
Can any of the quartz crystal gurus explain why this
frequency was chosen? I believe that this clock was
supposed to have better than usual accuracy.
Philips always had a h
I got in the GPSDO from China. It looks nice, but I have not tried firing it
up yet. I have no other info on this GPSDO. Here is what the seller has
found out. This GPSDO has two 10 MHz SMA connectors and a MMCX (?) antenna
connector. It has a 2007 date etched on a PCB. I suspect some of
Hi
Pretty much all of the GPSDO’s on eBay are long past their “end of support”
date. In a lot of cases, even
when “in support” free updates were not available, even to OEM customers. The
simple answer with the
TBolt is to run it into something (like Lady Heather ) that understands what’s
going
I have an elderly Trimble Thunderbolt that I use primarily as a
frequency reference. The date has never been correct (today, it reads
Aug 15, 1999), which probably resulted from the last rollover. Should I
anticipate any additional problems with the upcoming rollover?
This Thunderbolt has Appl
Replied off-list but suggestions welcome.
On Sun, Mar 31, 2019 at 6:00 PM Mod Mix wrote:
> Hi Adrian,
> sorry for cantacting you directly...
> I've got a pair of KS-24361 showing now the red FAULT led on just after
> applying power.
> As I don't know much about these electronics: could you pls
Hi Adrian,
sorry for cantacting you directly...
I've got a pair of KS-24361 showing now the red FAULT led on just after
applying power.
As I don't know much about these electronics: could you pls give me an
indication where to find a possibly failed tant?
Thank you in advance
Ulli
Am 24.02.20
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