[time-nuts] Re: Rooftop GNSS antenna mounting recommendations

[Dan Kemppainen]

Hi,

You haven't mentioned if you live in an are a with snow. (If you have a 
flat roof, my guess is maybe not). If that piles up like here, you may 
want to reach up a little higher to clear that.

A long time ago we used to install satellite dishes for remote classroom 
learning and medical training. These usually involved large (4ft) dishes 
mounted with non penetrating mounts. The mounts had several large 1/4" 
thick steel pads. Everything was galvanized plate steel and angle iron. 
We'd put a rubber material down, then the steel pad, then several 
hundred pounds of concrete blocks. The blocks were secured with banding 
to the pads.

The point wasn't if the dish would stay still, it was to keep it in 
place with 75mph or 100mph winds. Depending on your location, you may 
want to plan for worst case weather. Having the wind blow a concrete 
block off the roof onto your car or someone below is worth considering.

That said, I did have a 'roof mount' magnetic GPS antenna stuck to a 
rather large chunk of steel plate on a low pitch shingled roof for a few 
years. It stayed in place, but was in danger of getting shoveled off 
with the snow (We get 300+ inches a year). It worked fine for the half a 
dozen years it was there.

My recommendation would be something big and heavy, and low profile.

Dan






On 7/5/2023 3:30 AM, time-nuts-request at lists.febo.com wrote:
> Subject:
> [time-nuts] Rooftop GNSS antenna mounting recommendations
> From:
> Matt Huszagh <huszaghmatt at gmail.com>
> Date:
> 7/4/2023, 4:22 AM
> 
> To:
> Discussion of precise time and frequency measurement 
> <time-nuts at lists.febo.com>
> 
> 
> Hi,
> 
> I'll be mounting a GNSS antenna to my roof for timing applications and
> would appreciate recommendations for the best way to do this. The
> portion of the roof where the antenna will be mounted is flat. I'd
> prefer to avoid drilling or screwing into the roof if possible. But, if
> there's a safe and reversible way to do this, I'm ok with that.
> 
> I found a method described by sparkfun that involves using an anchor in
> a cinder block:
> 
> https://learn.sparkfun.com/tutorials/how-to-build-a-diy-gnss-reference-station/all#affix-your-antenna
> 
> This seems like an easy and low-cost method. Given the weight of the
> cinder block, I wouldn't expect the antenna to move. Thoughts? Any
> potential problems with this? Other methods that work well?
> 
> Matt