Re: NTP question

[Bryan Fields <Bryan () bryanfields net>]

On 5/1/19 3:22 PM, Mehmet Akcin wrote:
> hey there Nanog,
>
> I am trying to buy a GPS based NTP server like this one
>
> https://timemachinescorp.com/product/gps-time-server-tm1000a/
>
> but I will be placing this inside a data center, do these need an actual
> view of a sky to be able to get signal or will they work fine inside a data
> center building? 

You will need a clear view to the sky for at least the antenna.

Most GPS "antennas" are an antenna and Low Noise Amplifier (LNA) which is
powered via 5-12v on the coax.  This sets the noise figure and gain of the
system, so you can run 50-100' of RG6 coax if needed.  You'll need a F to sma
adapter for this unit it looks like.  Don't worry about the impedance
mismatch, 50 to 75 ohm is not horrid, the RG-174 thin cable has more loss in
10' than 100' of RG6.

You will not want to use the low gain puck antenna, but rather get a proper
grounded/mounted/weatherproofed antenna such as the ubiquitous 26 dBi
Quadrifilar Helix antenna. https://www.ebay.com/itm/192899151132



-- 
Bryan Fields

727-409-1194 - Voice
http://bryanfields.net