digital clock near cable box always gaining minutes per mont

[micky]

On Mon, 9 Mar 2015 16:38:37 -0700 (PDT), Phil Allison
<pallison49@gmail.com> wrote:

Pat wrote:

I am not talking about "atomic clocks". I am talking about regular
old clocks like people sit on their nightstands. Most of them sync to
the power line frequency. By most, I mean over 90%. Many have
battery backup and keep lousy time when running on battery.

I think it's unlikely that the cable box is interfering.

If the clock synchronizes with WWVL, the location may interfere
with acquiring that signal.


** Even that is very unlikely, given the OP's story, as the transmission is modulated with a code that regularly tells the clock what time it is.

Which is not consistent with a steady loss or gain.

I have a Philips DVDR** with a terrible clock. A digital video disk
recorder with a hard drive. It has 3 setting, auto, manual, and off.

Auto is supposed to sync to some signal on educational tv stations, or
maybe I mean public tv stations.

But what could be the difference between manual and off???? Do you or
anyone else here know?

**Something like DVDR6567R, or close to that.


No matter what the setting, the clock is often wrong, and I have to set
the timer to start a minute in advance and end a minute late. This
usually works, but of course doesn' if I want to record a program that
starts right after another on a different channel ends.

My friend bought a very similar machine, now sold under the name
Magnavox, and it too has a clock that works like mine, badly.

... Phil

 

[micky]

On Tue, 10 Mar 2015 17:26:07 -0400, micky <NONONOmisc07@bigfoot.com>
wrote:

On Mon, 9 Mar 2015 16:38:37 -0700 (PDT), Phil Allison
pallison49@gmail.com> wrote:

Pat wrote:

I am not talking about "atomic clocks". I am talking about regular
old clocks like people sit on their nightstands. Most of them sync to
the power line frequency. By most, I mean over 90%. Many have
battery backup and keep lousy time when running on battery.

I think it's unlikely that the cable box is interfering.

If the clock synchronizes with WWVL, the location may interfere
with acquiring that signal.


** Even that is very unlikely, given the OP's story, as the transmission is modulated with a code that regularly tells the clock what time it is.

Which is not consistent with a steady loss or gain.


I have a Philips DVDR** with a terrible clock. A digital video disk
recorder with a hard drive. It has 3 setting, auto, manual, and off.

Auto is supposed to sync to some signal on educational tv stations, or
maybe I mean public tv stations.

But what could be the difference between manual and off???? Do you or
anyone else here know?

**Something like DVDR6567R, or close to that.


No matter what the setting, the clock is often wrong, and I have to set
the timer to start a minute in advance and end a minute late. This
usually works, but of course doesn' if I want to record a program that
starts right after another on a different channel ends.

My friend bought a very similar machine, now sold under the name
Magnavox, and it too has a clock that works like mine, badly.

Even though I have the clock set to manual, it still changed the time
when DST started. I don't know if it changed it exactly an hour or if
it tried to use some time signal somewhere.

 

[Leif Neland]

micky har bragt dette til os:

On Mon, 9 Mar 2015 16:38:37 -0700 (PDT), Phil Allison
pallison49@gmail.com> wrote:



No matter what the setting, the clock is often wrong, and I have to set
the timer to start a minute in advance and end a minute late. This
usually works, but of course doesn' if I want to record a program that
starts right after another on a different channel ends.

You are lucky if the programs start at the announced time.

Here, usually the commercials and the advertisements of other shows
usually start at the announced time for the show.

Leif

--
Je suis Charlie

 

[Michael Black]

On Tue, 10 Mar 2015, micky wrote:

On Mon, 9 Mar 2015 16:38:37 -0700 (PDT), Phil Allison
pallison49@gmail.com> wrote:

Pat wrote:

I am not talking about "atomic clocks". I am talking about regular
old clocks like people sit on their nightstands. Most of them sync to
the power line frequency. By most, I mean over 90%. Many have
battery backup and keep lousy time when running on battery.

I think it's unlikely that the cable box is interfering.

If the clock synchronizes with WWVL, the location may interfere
with acquiring that signal.


** Even that is very unlikely, given the OP's story, as the transmission is modulated with a code that regularly tells the clock what time it is.

Which is not consistent with a steady loss or gain.


I have a Philips DVDR** with a terrible clock. A digital video disk
recorder with a hard drive. It has 3 setting, auto, manual, and off.

Auto is supposed to sync to some signal on educational tv stations, or
maybe I mean public tv stations.

It relied on the PBS station keeping the proper time. And that wasn't
always the case.

My DTV has "automatic", but I'm not sure where that's coming from. I
assume it's a different form than those VCR and DVD recorders. But it too
varies, it will change time with the station if the station has the wrong
time.

Michael

 

[micky]

On Wed, 11 Mar 2015 15:53:22 -0400, Michael Black <et472@ncf.ca> wrote:

On Tue, 10 Mar 2015, micky wrote:

On Mon, 9 Mar 2015 16:38:37 -0700 (PDT), Phil Allison
pallison49@gmail.com> wrote:

Pat wrote:

I am not talking about "atomic clocks". I am talking about regular
old clocks like people sit on their nightstands. Most of them sync to
the power line frequency. By most, I mean over 90%. Many have
battery backup and keep lousy time when running on battery.

I think it's unlikely that the cable box is interfering.

If the clock synchronizes with WWVL, the location may interfere
with acquiring that signal.


** Even that is very unlikely, given the OP's story, as the transmission is modulated with a code that regularly tells the clock what time it is.

Which is not consistent with a steady loss or gain.


I have a Philips DVDR** with a terrible clock. A digital video disk
recorder with a hard drive. It has 3 setting, auto, manual, and off.

Auto is supposed to sync to some signal on educational tv stations, or
maybe I mean public tv stations.

It relied on the PBS station keeping the proper time. And that wasn't
always the case.

My DTV has "automatic", but I'm not sure where that's coming from. I
assume it's a different form than those VCR and DVD recorders. But it too
varies, it will change time with the station if the station has the wrong
time.

What do you think the difference is between Off and Manual?. Even when
I have it on Off, I can still change the time manually

(that is, using the remote, going to time, putting in the numbers that
represent the time.) .

Michael

 

Michael Black wrote: "It relied on the PBS station keeping
the proper time. And that wasn't "

I live within 40 miles of three PBS affiliates, and while
my rooftop setup is strong enough to pull in steady
picture and sound, a lot of times I still don't get the
meta(title and description of the program currently
showing), let alone time correction.

I also wish this 'smart' Samsung LED had a way to view
signal strength the way my ChannelMaster CM7000
converter box did.

 

[Pat]

On Sun, 15 Mar 2015 04:16:05 -0700 (PDT), thekmanrocks@gmail.com
wrote:

Michael Black wrote: "It relied on the PBS station keeping
the proper time. And that wasn't "

I live within 40 miles of three PBS affiliates, and while
my rooftop setup is strong enough to pull in steady
picture and sound, a lot of times I still don't get the
meta(title and description of the program currently
showing), let alone time correction.

I have only been half following this thread, but I thought the PBS
(public TV is the US) time setting thing was a feature added to analog
broadcasts. It certainly started that way. They added some bits in
the retrace portion of the NTSC signal. Did the feature somehow
survive the analog to digital transition?

Pat

 

[Michael Black]

On Sun, 15 Mar 2015, Pat wrote:

On Sun, 15 Mar 2015 04:16:05 -0700 (PDT), thekmanrocks@gmail.com
wrote:

Michael Black wrote: "It relied on the PBS station keeping
the proper time. And that wasn't "

I live within 40 miles of three PBS affiliates, and while
my rooftop setup is strong enough to pull in steady
picture and sound, a lot of times I still don't get the
meta(title and description of the program currently
showing), let alone time correction.


I have only been half following this thread, but I thought the PBS
(public TV is the US) time setting thing was a feature added to analog
broadcasts. It certainly started that way. They added some bits in
the retrace portion of the NTSC signal. Did the feature somehow
survive the analog to digital transition?

That was the point. We were told to use a PBS station since it was either
the stations that had the time feature, or the most likely ones (I don't
know if it ever propogated to commercial stations).

DTV sets do have "auto" when keeping time, so I've assumed the DTV
standard includes a timecode somewhere. I know it works on various
stations, though as I said, the station has to keep proper time. Every so
often the time gets skewed, and it's because of one station.

But I am assuming the DTV arrangement is different from the analog time
system.

Michael

 

[Phoena Greene]

On 03/09/2015 10:34 AM, Sam Seagate wrote:

> Is there anything I can to do get more accuracy?

Well since you're 100 percent certain that it is the cable box when why
not disconnect and unplug the cable box and go out and beat tweakers
with it. At least until you can determine that it actually was the cable
box that was throwing your clock out of whack.

BTW: Doesn't the cable box have a clock of it's own? A more accurate
self setting clock like most cable boxes made in the past 20+ years?

 

[Michael A. Terrell]

Michael Black wrote:

On Sun, 15 Mar 2015, Pat wrote:

On Sun, 15 Mar 2015 04:16:05 -0700 (PDT), thekmanrocks@gmail.com
wrote:

Michael Black wrote: "It relied on the PBS station keeping
the proper time. And that wasn't "

I live within 40 miles of three PBS affiliates, and while
my rooftop setup is strong enough to pull in steady
picture and sound, a lot of times I still don't get the
meta(title and description of the program currently
showing), let alone time correction.


I have only been half following this thread, but I thought the PBS
(public TV is the US) time setting thing was a feature added to analog
broadcasts. It certainly started that way. They added some bits in
the retrace portion of the NTSC signal. Did the feature somehow
survive the analog to digital transition?

That was the point. We were told to use a PBS station since it was either
the stations that had the time feature, or the most likely ones (I don't
know if it ever propogated to commercial stations).

DTV sets do have "auto" when keeping time, so I've assumed the DTV
standard includes a timecode somewhere. I know it works on various
stations, though as I said, the station has to keep proper time. Every so
often the time gets skewed, and it's because of one station.

But I am assuming the DTV arrangement is different from the analog time
system.

PBS transmitted the time code in the vertical retrace, where VIR and
VITS are also transmitted on other horizontal lines. The CRT was blanked
during this time, but on some sets you could see these signals at the
top of the screen by reducing the height of the display.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

 

[micky]

On Sun, 15 Mar 2015 12:28:20 -0400, Michael Black <et472@ncf.ca> wrote:

On Sun, 15 Mar 2015, Pat wrote:

On Sun, 15 Mar 2015 04:16:05 -0700 (PDT), thekmanrocks@gmail.com
wrote:

Michael Black wrote: "It relied on the PBS station keeping
the proper time. And that wasn't "

I live within 40 miles of three PBS affiliates, and while
my rooftop setup is strong enough to pull in steady
picture and sound, a lot of times I still don't get the
meta(title and description of the program currently
showing), let alone time correction.


I have only been half following this thread, but I thought the PBS
(public TV is the US) time setting thing was a feature added to analog
broadcasts. It certainly started that way. They added some bits in
the retrace portion of the NTSC signal. Did the feature somehow
survive the analog to digital transition?

That was the point. We were told to use a PBS station since it was either
the stations that had the time feature, or the most likely ones (I don't
know if it ever propogated to commercial stations).

DTV sets do have "auto" when keeping time, so I've assumed the DTV
standard includes a timecode somewhere.

Me too, but now I wonder where. When the antenna amplifier is not
working, I can't get any PBS station well. Yet it did change the time
a few days ago when DST ended.

I know it works on various
stations, though as I said, the station has to keep proper time. Every so
often the time gets skewed, and it's because of one station.

But I am assuming the DTV arrangement is different from the analog time
system.

I knew no better and assumed it was the same, but I gather it's not.

Where, oh where has the time gone?

> Michael

 

[micky]

On Mon, 09 Mar 2015 21:23:26 -0700, isw <isw@witzend.com> wrote:

In article <mdks25$726$1@dont-email.me>, mike <ham789@netzero.net
wrote:

On 3/9/2015 6:45 AM, Pat wrote:
On Mon, 09 Mar 2015 06:34:52 -0400, Sam Seagate
sseagate55094@yahoo.com> wrote:

I have three digital clocks in my home that are located in various
rooms. Two of them have accurate timing and may gain or lose a minute
in a year, but the one in the living room near the cable box/ tv gains
3-4 minutes a month. My guess is that its frequency circuit is
interfered with from the cable system. First instinct would be to move
the clock, but unfortunately there is limited space and I can't. Is
there anything I can to do get more accuracy? During my initial
research, I came across postings suggesting adding a low pass filter on
the incoming line to the clock, but not sure.

Any helpful suggestions would be welcome.

Thanks,
Sam

Most inexpensive clocks count the cycles (frequency) of their power
source. Excessive noise on the line can cause extra cycles to be
counted. The power supply in the cable box could be adding noise to
the power line. If so, a filter can help with that. Technically, it
would be a low pass filter (as you said) because it lets through the
60 Hz (or 50 Hz) power, but filters the higher frequency noise.
However, you might have trouble finding something appropriate called
that because the term loss pass filter is used for RF applications.
Search for power line noise filters.

I don't doubt that you can come up with an example, but I think it's
unlikely that the average digital clock works that way.

If the clock is in a box that plugs into an outlet (oven, microwave, TV,
VCR back in the day), odds are that it counts cycles of the power line.

It's easy to tell; just set it precisely and then monitor it for a few
weeks. If it keeps "perfect" time, it uses the power line; if it slowly
drifts ahead or behind, it's using a crystal for a time base.

Isaac

Yes. AIUI, because of things related to speed regulation of dynamos,
the frequency of the power line current does occasionally run too fast
or slow by a portion of a second or more, but they keep track and make
it do the opposite so that the time signal averages out correctly.

 

micky wrote: "Me too, but now I wonder where.
When the antenna amplifier is not
working, I can't get any PBS station well. Yet it did
change the time a few days ago when DST ended. "


Uhh micky, DST just STARTED a couple weeks ago.
Notice how dark it is at morning and how light it is
past dinner?


(One more reason to abolish it: The average citizen
doesn't know Standard from Savings, and what they're
supposed to do at the beginning of each!)

 

[Jeroni Paul]

Some clocks have a variable capacitor next to the crystal to fine tune the time keeping. To adjust them I use this web as a time reference http://time.is
One day is enough to check if it is good enough, a deviation of less than 1 second a day are less than 3 minutes in 6 months. You can get better using longer time spans.
I dessisted to use cheap atomic clocks for that. For some reason when they sync they keep a variable deviation of some seconds, that is not good enough for a 1 day check of another clock.

 

[CW]

On Tuesday, March 10, 2015 at 7:43:15 AM UTC-4, Leif Neland wrote:

Phil Allison sendte dette med sin computer:
Pat wrote:

I am not talking about "atomic clocks". I am talking about regular
old clocks like people sit on their nightstands. Most of them sync to
the power line frequency. By most, I mean over 90%. Many have
battery backup and keep lousy time when running on battery.

I think it's unlikely that the cable box is interfering.

If the clock synchronizes with WWVL, the location may interfere
with acquiring that signal.


** Even that is very unlikely, given the OP's story, as the transmission is
modulated with a code that regularly tells the clock what time it is.

Which is not consistent with a steady loss or gain.

Unless the clock is unable to synchronize, and therefore are
free-running.

My digital radio-controlled clocks are only sync'ing once every 24
hours, usually at 3am, where the radiowaves supposedly travel the best
and the noise is the lowest.

Btw, I've had an analog (i.e. with hands, not digits) clock.
It's funny to see it change time in and out of DST; the hands spin
around like crazy, moving either 1 or 11 hours ahead in a few minutes.

Leif

--
Je suis Charlie

We have analog clocks with a motor for each hand. They accept external SMPTE timecode. Plug them in and the hands move CW or CCW to the proper time. They take less than 20 seconds to set themselves.

 

[Leif Neland]

CW udtrykte prĂŚcist:

On Tuesday, March 10, 2015 at 7:43:15 AM UTC-4, Leif Neland wrote:


Btw, I've had an analog (i.e. with hands, not digits) clock.
It's funny to see it change time in and out of DST; the hands spin
around like crazy, moving either 1 or 11 hours ahead in a few minutes.

Leif

--
Je suis Charlie

We have analog clocks with a motor for each hand. They accept external SMPTE
timecode. Plug them in and the hands move CW or CCW to the proper time. They
take less than 20 seconds to set themselves.

Good for you ;-)

What's the reason for this? Theater use? Resetting the clocks for
movie/TV recording?

Why this extra cost?
My analog clock resets the hands to 12-o'clock after battery change (it
only knows when the hands are "home", it does not have an angular
encoder or something.
After the hands are home, the hands moves fast to the correct time, but
with the usual speed ratio between seconds, minutes and hour-hands.

Leif

--
Je suis Charlie