better than the old
Accutron ever did!
Encouraging regards,
Lee
- Original Message -
From: "Alexander Pummer"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, September 13, 2014 6:44 AM
Subject: Re: [time-nuts] Is a crystal likely to cha
there is only one magnet, which drives the fastest moving arm -- the
pointer for the seconds -- the other arms are connected via gears, by
the way that case with the weak periodically recovering battery is an
observed one, I connected a paper chart recorder to the clock and
recorded the bat
Hi
In this era of “everything runs at GHz” it’s a bit tough to reach back to the
sort of process used for watch IC’s.
The idea is to optimize for low power / low leakage. They make enough of them
that an application specific process can be used. The divide side of the chip
may have an Fmax of
On Sat, Sep 13, 2014 at 8:08 AM, Dr. David Kirkby (Kirkby Microwave Ltd) <
drkir...@kirkbymicrowave.co.uk> wrote:
> So if it the mechanics skips a pulse, one really needs some method of
> measuring the position of the hands and recording that.
>
Better modern quartz movements, have circuitry in
On 13 Sep 2014 04:39, "David McGaw" wrote:
>
> The battery probably was going weak and the oscillator coming out of full
control by the crystal. The tuning-fork crystal used in RTCs is not as
high-Q as a MHz crystal. I have noticed clocks using these can go quite
slow at low voltage. The crysta
On 13 Sep 2014 01:23, "Alexander Pummer" wrote:
>
> just open the box, look for the wires which going to the magnet which
drives the minute hand and measure the period time -- not the frequency, it
is to low
> yes analog quarz clock slows down as the battery get old, you will be
surprised, that t
The battery probably was going weak and the oscillator coming out of
full control by the crystal. The tuning-fork crystal used in RTCs is
not as high-Q as a MHz crystal. I have noticed clocks using these can
go quite slow at low voltage. The crystal acts more like an inductor in
this case an
just open the box, look for the wires which going to the magnet which
drives the minute hand and measure the period time -- not the frequency,
it is to low
yes analog quarz clock slows down as the battery get old, you will be
surprised, that the driver pulse's period time dos not change, but
s
Dr David Kirkby
Managing Director
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Chelmsford, Essex, CM3
6DT, United Kingdom
Registered in England and Wales as company number 08914892
http://www.kirkbymicrowave.co.uk/
Tel 07910 441670 / +44 7910 441670 (0900-2100 GMT)
On 12 S
Hi
If this is an RTC, it’s probably running off of a battery when the machine is
powered down. It is far more likely that the oscillator is dropping out
(stopping) rather than shifting frequency. One way it might do this is to stop
for a relatively brief period, battery recovers, and then start
On 12 Sep 2014 03:35, "Alex Pummer" wrote:
>
> No that is to much, except if you overdrive it and you are so lucky that
after it broke it is still working on a different frequency, but I would
suggest check your frequency counter too, because 3% off of a clock
frequency wold make the clock almost
No that is to much, except if you overdrive it and you are so lucky that
after it broke it is still working on a different frequency, but I would
suggest check your frequency counter too, because 3% off of a clock
frequency wold make the clock almost unusable not just for time nuts...
73
KJ5UHN
On 26 Nov 2012 14:12, "David Kirkby" wrote:
>
> I've got an HP 8720D VNA. This has been out of support from Agilent
> for 8 years, so its getting on a bit. There's a clock in the
> instrument which keeps the date and time. This is losing about 1 day
> per month (rough guess), so it has slowed by a
On 26 November 2012 16:00, J. Forster wrote:
> Have you contacted ArtekMedia for any manual information?
No. First I'll try to get a free one!
> Also, have you checked/posted a question to the VNA Agilent Forum?
Yes. Only a few hours ago (just before I posted on time-nuts I think),
so still cha
Have you contacted ArtekMedia for any manual information?
Also, have you checked/posted a question to the VNA Agilent Forum?
-John
==
> I've got an HP 8720D VNA. This has been out of support from Agilent
> for 8 years, so its getting on a bit. There's a clock in the
> instrument wh
[mailto:time-nuts-boun...@febo.com] On
Behalf Of David Kirkby
Sent: Monday, November 26, 2012 9:12 AM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] Is a crystal likely to change frequency by 3% ?
I've got an HP 8720D VNA. This has been out of support from Agilent
for 8
David
Try here, they have the service guide but no component level info
available that I can see.
_http://na.tm.agilent.com/8720/document.htm_
(http://na.tm.agilent.com/8720/document.htm)
Regards
Nigel
GM8PZR
In a message dated 26/11/2012 14:12:55 GMT Standard Time,
david.ki
I've got an HP 8720D VNA. This has been out of support from Agilent
for 8 years, so its getting on a bit. There's a clock in the
instrument which keeps the date and time. This is losing about 1 day
per month (rough guess), so it has slowed by a bit over 3%.
I'm guessing this is likely to be a batt
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