maybe he should switch to Number Juan Tequila
http://numberjuantequila.com/

Jaime Solorza
Wireless Systems Architect
915-861-1390

On Wed, Aug 12, 2015 at 11:54 AM, Bill Prince <[email protected]> wrote:

> It's all that vodka.
>
> bp
> <part15sbs{at}gmail{dot}com>
>
>
> On 8/12/2015 10:52 AM, Vlad Sedov wrote:
>
> Having lived around Soviet RFs for many years, I can tell you first hand
> that they are the laziest RFs with the worst work ethic.
>
>
> Vlad
>
> On 8/12/2015 12:42 PM, Mathew Howard wrote:
>
> We don't need any stinkin' commie RF!
>
> Добрий День товарищ!
>
> On Wed, Aug 12, 2015 at 12:36 PM, Shayne Lebrun <[email protected]>
> wrote:
>
>> Nyet, Tovarich.  Superior SOVIET RF works four times as hard as any lazy
>> capitalist RF, and without exploiting the proletariat photons.
>>
>>
>>
>>
>>
>>
>>
>> *From:* Af [mailto:[email protected]] *On Behalf Of *Jaime Solorza
>> *Sent:* Wednesday, August 12, 2015 1:22 PM
>> *To:* Animal Farm
>> *Subject:* Re: [AFMUG] GPS Timing
>>
>>
>>
>> not to worry Comrade   RF is universal
>>
>>
>> Jaime Solorza
>>
>> Wireless Systems Architect
>>
>> 915-861-1390
>>
>>
>>
>> On Wed, Aug 12, 2015 at 9:52 AM, George Skorup < <[email protected]>
>> [email protected]> wrote:
>>
>> Cambium is using a new receiver on the 450APs that does GPS+GLONASS. I
>> assume it's from Global-Top, but I haven't opened up a new AP to look. I'm
>> not real excited about using the Russian signals, but with so many
>> satellites available, it does acquire lock very fast. Have you thought
>> about doing the same for your 'Pipes? I think it would be beneficial.
>>
>>
>>
>> On 8/12/2015 5:34 AM, Forrest Christian (List Account) wrote:
>>
>> Ok, if you really want to know, I finally found a (somewhat data)
>> document which describes this in semi-understandable terms.
>>
>> And yes, the real time does fall out of the equations (see watch error -
>> which is how fast or slow your reference clock is).
>>
>> http://www.maa.org/sites/default/files/pdf/cms_upload/Thompson07734.pdf
>>
>> What I'm hearing from my GPS module vendor is effectively that since they
>> don't really have to do any additional work to output a 1PPS signal from a
>> 3d lock, they feel comfortable in doing so.   Adding the complexity of
>> surveying an location to an useful accuracy and then using that to compute
>> the time is a lot of additional work with a lot of variability they don't
>> want to try to deal with without additional demand.   I do know that a
>> while back we tried some shortcuts to get there, but they were not all that
>> useful.
>>
>>
>>
>> -forrest
>>
>>
>>
>> On Tue, Aug 11, 2015 at 12:25 PM, Sean Heskett < <[email protected]>
>> [email protected]> wrote:
>>
>> the satellites are constantly moving tho and since they are moving faster
>> in orbit than we are here on earth you need to account for relativity.
>>  knowing where you are doesn't give you enough information to know where
>> the satellite is and therefore you can't accurately calculate the
>> relativity offset.  once you have 3D lock with 4 satellites you can
>> accurately calculate the relativity offset and therefore calculate the
>> accurate time for where you are on earth.
>>
>>
>>
>> shoulda taken the blue pill ;-)
>>
>>
>>
>> -Sean
>>
>>
>>
>> On Tue, Aug 11, 2015 at 12:08 PM, Bill Prince < <[email protected]>
>> [email protected]> wrote:
>>
>> That's what I thought too. Once one of these little beggars has been
>> online for a half hour or more, the location should be "set" so to speak. I
>> would then expect them to hold time sync even with 1 satellite in view.
>> Knowing that the location is static and unmoving, I would expect that
>> maintaining time lock would be gravy.
>>
>> Sadly, this does not seem to be the case.
>>
>>
>> bp
>>
>> <part15sbs{at}gmail{dot}com>
>>
>>
>>
>> On 8/11/2015 10:48 AM, Chuck McCown wrote:
>>
>> Interesting, I guess you need to know where you are to calculate the
>> delay.  Had not considered that.  But if you know where you are and have
>> ephermis data, you should be able to calculate the delay and arrive at a
>> pretty accurate timing pulse with one satellite.
>>
>>
>>
>> *From:* Forrest Christian (List Account) <[email protected]>
>>
>> *Sent:* Tuesday, August 11, 2015 11:39 AM
>>
>> *To:* af <[email protected]>
>>
>> *Subject:* Re: [AFMUG] GPS Timing
>>
>>
>>
>> You need an accurate  3d position to get accurate timing.   To have an
>> accurate 3d position using GPS alone, you need four satellites.  Three
>> only gets you a 2d lock, and less than that you don't get a lock at all.
>>
>> There are receivers out there which will survey a position and then use
>> that position to be able to continue to provide a timing signal if you
>> subsequently lose lock but still have sats in view.   As far as I know,
>> this type of receiver is not in use in any commercially available timing
>> product for the cambium radios.  In fact I think we've almost all ended up
>> using the exact same GPS modules, at least for any recently designed
>> product.
>>
>> Some of the earlier products would attempt to preserve the sync signal
>> across a GPS lock loss with various levels of success.   For instance the
>> cmm micro in early releases provided a wildly incorrect sync pulse even
>> without a lock.   Same with early syncpipes.  The CTM has a holdover
>> timer.  And so on.   I think most of us have moved away from this in newer
>> designs.
>>
>> On Aug 11, 2015 8:36 AM, "Dan Petermann" < <[email protected]>
>> [email protected]> wrote:
>>
>> What is the minimum amount of satellites needed for a proper GPS sync
>> pulse?
>>
>> And does that differ across products (CMM, CTM, SyncPipe, etc.)?
>>
>>
>>
>>
>>
>>
>>
>>
>> --
>>
>> *Forrest Christian* *CEO, PacketFlux Technologies, Inc.*
>>
>> Tel: 406-449-3345 | Address: 3577 Countryside Road, Helena, MT 59602
>>
>> <[email protected]>[email protected] | http://www.packetflux.com
>>
>> <http://www.linkedin.com/in/fwchristian>
>> <http://facebook.com/packetflux>  <http://twitter.com/@packetflux>
>>
>>
>>
>>
>>
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