[time-nuts] WWVB Wall and Travel Clocks On Sale

[Ed Palmer]

I see.  The Hummer clock has a single xtal circuit.  When I tried to 
monitor it with a scope just now, even in A-B mode with x10 probes, the 
data was trash and the clock gives up after about 5 minutes.  But if I 
leave it alone, it only takes a few minutes to lock in.  Same with a 
couple of other cheap clocks.  I remember that later in the evening when 
the signal is stronger, I could monitor it with an analog scope with no 
problem.  You could decode it just by looking at it.

Ed


Brooke Clarke wrote:
> Hi Ed:
>
> Yes, the one shown on Tom's web page:
> http://leapsecond.com/pages/sony-wwvb/
> uses two 60 kHz crystals in the filter rather than the single crystal 
> like in the C-max CMMR-6P-60 (Digi-Key p/n:  561-1014-ND) that uses a 
> single crystal. C-Max is the new name for Temic that made the chip in 
> Tom's clock.
>
> http://www.prc68.com/I/Loop.shtml#CMMR6P60
>
> I connected the CMMR-6P-60 to a couple of AA batteries and it's been 
> blinking for the last month or two.  But that data is very noisy.
>
> Have Fun,
>
> Brooke Clarke
> http://www.prc68.com
>
> Ed Palmer wrote:
>> Hi Brooke,
>>
>> Is there something special about the Sony clock that you want?  
>> Before I found out about Time Nuts & GPSDOs I was looking at using 
>> one of these "atomic clocks" as a source of time and /or frequency.  
>> Most of them have a point where you can get to the time code.  
>> Getting to the 60 KHz carrier was a bit trickier.
>>
>> e.g. I picked up a few Hummer Atomic Clocks on clearance for about 
>> $5.  The radio is a seperate unit that sends out the time code 
>> continuously.  The clock takes about 5 minutes to lock in.  I'm about 
>> 680 miles from Fort Collins.
>>
>> Ed
>>
>> Brooke Clarke wrote:
>>> Hi Tom:
>>>
>>> I've looked at dozens of Sony "Dream Machine" clocks on eBay and 
>>> none of them have WWVB capability.   Some are called preset or self 
>>> setting, but these may just be using a button cell back up clock.
>>>
>>> What is the model number of your Sony WWVB clock?
>>>
>>> Have Fun,
>>>
>>> Brooke Clarke
>>> http://www.prc68.com
>>>
>>> Mike Monett wrote:
>>>  
>>>> Update on my previous post - tvb has a nice page on WWVB receivers at
>>>>
>>>> http://leapsecond.com/pages/sony-wwvb/
>>>>
>>>> Looks like these receivers might make good wall clocks.
>>>>
>>>> But for checking GPSDO's - not so good:)
>>>>
>>>> Regards,
>>>>
>>>> Mike
>>>>     
>>
>>
>