[time-nuts] Re: GPS failed

[Chris Caudle]

On Sun, July 10, 2022 6:19 pm, skipp Isaham via time-nuts wrote:
> Background:  Three different hill-top GPS receivers, all different types,
> using
> different antennas mounted on an outside fixiture, plain view of the open
> sky,
> all stopped working.
>
> Test antennas were brought in and placed on a fixture well away from the
> original antennas, the recevers went back in to capture and lock.

Did you test the original antennas in a different environment to see if
they still work at all?  Perhaps the amplifier in the antenna housing
failed on the original three antenna.

> I would suspect a GPS antenna (and receiver) could be subject to RF
> overload
> or blocking, however, we're assuming nothing major has changed at the
> site, nor
> any nearby location.

If you are implying that you think the antenna are still working, but
cannot handle the RF environment at that location which is what caused the
GPS failure, I would be dubious.  You said hilltop location, so my first
suspicion would be damage to the antenna induced by a nearby lightning
strike.

>  One might think there are more GPS receivers being
> pushed
> out of reliable operation by the world around them, I'm just not hearing
> those stories
> from a lot of people using them (GPS receivers).

Spectrum allocation is controlled reasonably tightly.  If there were
widespread problems due to increased EMI then you would know relatively
quickly from the number of people using GPS every day.

-- 
Chris Caudle