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Wireless geek
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Iron
Re: WWV clocks
Wireless geek   9/6/2013 10:47:14 AM
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Generally speaking, I have a feeling that almost everywhere outdoors, and far from strong interferers, reception is usually successful.   It is interesting to hear about your experience with your wristwatch.  I have a Casio "Waveceptor" and it works well only as long as I am not staying at one of those larger hotels (tall buildings, based on concrete/steel frames). The small Holiday Inns are ok.   The losses in penetrating large buildings appear to be more challenging than the propagation losses for this 60kHz signal.   Anyway, with the new system being a few orders of magnitude better, everything should work in buildings too.   By the way, I recently went hiking in the beautiful Rockies (you lucky Colorado native!) and was in Fort Collins as well.  My experience with a small WWVB alarm clock was that it didn't work in Fort Collins itself!   That's probably because the AM receiver was saturated.  Once shielded/distanced, it worked ok.  It's interesting that these products fail at both ends of the signal-level range that can be found within the USA.  The newer ones should not. 

 

Colorado Native
User Rank
Silver
Re: WWV clocks
Colorado Native   9/6/2013 10:25:00 AM
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Wireless Geek:

Of course I know the WWVB (and all of their time signals) is broadcast from Fort Collins, I do not recall saying (or indicating) I was "surprised to receive it so well".  For that matter I have received their signal from Hawaii as well as Fort Collins (shortwave radio of course, transmitted on several frequencies).  While there well may be possible reception problems in N.Y., you obviously do not know how the Rockies can interfere with signal reception, even if it is in the "backyard".

Depending on atmospheric conditions, the signal, even relatively close to the transmitter, can be difficult to reliably receive, add in other intereference and you may not be able to receive the signal reliably at all.  Poor antenna design in some of these clocks certainly do not help, a cheap stick antenna will often not be up to the task.  Do not blame the source in all cases, as mentioned in another comment, steps have been taken to try to improve the 'clarity' of the signal content in weak reception areas.

My wristwatch has not had any problems syncing with WWVB anywhere I have traveled as yet but I haven't been out of the USA with it yet.

Mydesign
User Rank
Platinum
Re: Self-Timing Clock
Mydesign   9/6/2013 4:19:36 AM
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1 saves
"But don't worry!  NIST realized that these problems are common and introduced a new broadcast format last year (check out their website), so we should expect that new products will be better behaved.   "

Wireless geek, hope for the best and there is no doubt that it can get much improved by new technologies.

Mydesign
User Rank
Platinum
Re: Self-Timing Clock
Mydesign   9/6/2013 4:15:22 AM
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1 saves
"Most of the clock like this that I've seen work like "normal" digital clocks when they don't see an adequate signal. Holding the current time makes a lot more sense than randomly setting the time."

Jcj, most of the clocks works either on single or dual power sources. If there is no solar power, it will get feed by the battery power.

Wireless geek
User Rank
Iron
Re: Self-Timing Clock
Wireless geek   9/6/2013 12:42:53 AM
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Yes, of course it should coast until it is sure about the reception quality.  "Monkeys" you're saying?!   This should be obvious enough to monkeys too...

I made the same observation on a radio-controlled clock in my office -  in 2012 it suddenly became '92 for a few days...  I thought that it took me 20 years back in time, but it was acutally 80 years into the future...  Isn't time-traveling exciting? 

But don't worry!  NIST realized that these problems are common and introduced a new broadcast format last year (check out their website), so we should expect that new products will be better behaved.   

Wireless geek
User Rank
Iron
Re: WWV clocks
Wireless geek   9/6/2013 12:34:16 AM
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Colorado Native, didn't you know that the WWVB broadcast also comes from Fort Collins, where the WWV signal comes from?   If so, why are you so surprised to recieve it well in the Rockies?   You are practically in the station's back yard there...   Now let me know how you're receiving it in NY...   Good luck!    

Wireless geek
User Rank
Iron
Re: Self-Timing Clock
Wireless geek   9/6/2013 12:31:43 AM
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2 hours slow?! If your radio-controlled clock shows MST instead of your time zone, it is becuase you selected the wrong time zone (and/or also got the daylight-saving time enable/disable switch in the wrong position).   The time broadcast from Colorado is not MST but UTC and the products are all capable of calculating the time offset to your time-zone (at least between EST and PST). 

These low-cost products may have pathetic performance in terms of reception reliability (at least until receivers for the new broadcast replace the old ones), but there shouldn't be a problem with the time zone.  

 

 

 

tucsonics
User Rank
Silver
Re: Self-Timing Clock
tucsonics   9/6/2013 12:22:40 AM
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Thanks for all the comments! It's nice to know that I wasn't alone. The most obvious solution to my problem was to move the clock to a different wall, but it was a case of the tail wagging the dog! I wanted the clock where I could see it conveniently. I don't know if the low frequency signal would be impeded by the wire mesh they apply to the exterior stucco walls. I do know that leaving the clock by the window overnight effects the reset. As a designer of phase-lock loops for electronic warfare applications, it was standard procedure to enable the local clock to coast in both frequency and phase at the last known correction when the reference was lost. I guess the clock designers didn't have the fail-safe idea in mind.

bobjengr
User Rank
Platinum
SELF-TIMING CLOCK
bobjengr   9/5/2013 5:42:54 PM
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Very interesting post Michael.   Our house was build in 1953 and was designed for ceil heat.  With that being the case, we have electrical conductors in the floors and ceiling of each room.   I have long since "cut this system loose" and installed a central heating and air conditioning system.  In other words, no ceil heat although I still have the wires embedded.  With that being the case, I have also experienced difficulties with "self-timing" clocks and with cell phone reception.  The best reception for my cell phone comes when I'm in the front yard.  I was told by an EE friend of mine the previous heating system was the cause.  Can anyone comment on that one? 

Colorado Native
User Rank
Silver
WWV clocks
Colorado Native   9/5/2013 3:03:44 PM
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I've owned several La Crosse Technology clocks over the last ten years, my first was (and is) a wrist watch which has kept time quite well, the only 'bug' is that the battery only lasts about 11 months and every time you change it, it takes most of the night to regain the correct time and date.  Sometimes, if it takes a bit too long to change the battery, you may have to tell it what zone you are in, which is easy enough.  It has been able to hold the signal even driving through the Rockies.

I also have two different wall clock models, both of which act a bit differently when the batteries are changed.  One only needs the time zone reset afterwards but the other one sometimes requires more than the time zone to be reset for some reason but sooner or later, sometimes a day, it 'catches up' and always maintains time until the next battery change.  I have also given a La Cross to my Mother-in-Law which is on a wall (East-West) and it does not have a problem with the signal either.

It would appear that the design of the antenna/front end of these troublesome clocks is lacking a bit and needs improvement.  The only drawback I've seen in my 'atomic' clocks is that they take several hours to resync when the signal is interrupted.

I've also monitored WWV Fort Collins for years without any trouble receiving their time signals and I've got 250 miles of mountains between us.

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