[time-nuts] Inexpensive modular gps with 1pps

[Jim Lux]

On 11/15/12 5:33 AM, David wrote:
> On Thu, 15 Nov 2012 05:02:54 -0800, Jim Lux <jimlux at earthlink.net>
> wrote:
>
>> On 11/15/12 4:30 AM, David J Taylor wrote:
>>> i just used this to with a raspberry pi with good success.
>>>
>>> https://www.adafruit.com/products/746
>>>
>>> james
>>> ===============================================
>>>
>>> It looks idea, James, but ... with the 15 mm square patch antenna it
>>> seems deaf compared to similar devices with 25 mm antennas.  Perhaps
>>> understandable, but I just bought one and it's been sitting for well
>>> over an hour and not yet acquired lock.  The device I bought from China,
>>> sitting next to it, has been happily locked for that whole period.  (As
>>> I'm running a test I don't want to unlock the other device).  Just a
>>> caveat for someone considering using these devices indoors - size matters!
>>>
>>> 25 mm antenna device:
>>>    http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg
>>>    http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html
>>>
>>> Cheers,
>>> David
>>
>>
>> ALl good ideas.. but I was looking more for something a bit more
>> packaged.. like a hockey puck with wires coming out.
>
> I picked up a used Garmin GPS18-5Hz hockey puck to play with and after
> updating the firmware, have gotten good results with the cable going
> out a window and the unit sitting on the lower edge of the roof.  Its
> 5 pulse per second output has 60ns of resolution according to the
> Racal Dana 1992 I repaired implying about a 16.6 MHz timing clock.
>

That's the kind of thing I'm looking for.. or the Synergy TrakPuck  ... 
or one of those pods that came with mapping software 5-10 years ago.
I wonder if there's a new version of the GPS18, since I need something 
that is available off the shelf (and likely to remain so for at least 
2-3 years)..

Is there a timing output on the GPS16x?  (or are the serial messages 
synchronized in some way)