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

[Joseph Gwinn]

time-nuts Digest, Vol 231, Issue 4
On Wed, 05 Jul 2023 03:30:13 -0400, time-nuts-request at lists.febo.com 
wrote:
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Tue, 4 Jul 2023 01:22:53 -0700
> From: Matt Huszagh <huszaghmatt at gmail.com>
> Subject: [time-nuts] Rooftop GNSS antenna mounting recommendations
> To: Discussion of precise time and frequency measurement
> 	<time-nuts at lists.febo.com>
> Message-ID:
> 	<CA+X8ke5+yyTj9uwRKR_0+MZHZV+d6Bj-Qy==wEwJNMqhoYFdZA at mail.gmail.com>
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> 
> 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?

Tell us more about the flat roof, and also where this will be 
installed.

Flat roofs come in some varieties:  Tarpaper, EPDM rubber, galvanized 
steel, copper, and so on.  Slope?

As for ensuring that fastener hardware doesn't rust together, the 
best approach is to use stainless steel screws with brass nuts (or 
vice versa).  This combination will not rust together no matter 
what.  Loctite will ensure that it won't unscrew itself, but can be 
disassembled with a paint-stripping heat gun.

As for attaching to cinder blocks, the easiest way is to drill a 
through hole and attach using stainless steel screws, fender washers, 
and brass nuts.  One can also epoxy grout a threaded stainless steel 
insert into the cement block, but this is far more work.

Joe Gwinn