I have the opportunity to observe NOS 844 7505 D, PID AB7964.
It is on the edge of a bridge abutment and the bridge will be torn down next month.
The bridge is 'the last wooden drawbridge in the US' (as stated by 'historical' advocates). The silly setup is because of the bounce in the bridge with every passing car and that mark is on the edge.
I plan for ~6 hours of data. I also plan to share by data on OPUS. I usually do not share. Do you?
I've Occupied A Few Bridges
You have to stand right at the setup and when a concrete or dump truck crosses 20 mph over the speed limit be prepared to pluck your setup out of the air and quickly reset and plumb it. And never take your eye off of oncoming traffic.
Once I had to pick it off the pavement as I was behind the parapet relieving myself. Less than 2 minutes so the processor accepted the few bad observations.
Paul in PA