Sam the Centipede wrote: ↑Mon Jan 15, 2024 5:34 am
On a humdrum level it's the same with phones etc.: what's the point in learning to take bearings with a compass and determine one's position on a map or chart if your phone will tell you where you are? At the same time, it can tell you what's on the lunch menu at the pub you're heading for, and whether your friends have arrived yet.
I love technology, I love stories, and I have a story about plain old fashioned compasses.
I don't have my notes in front of me, but I want to say this happened during the Obama years when there were plenty of infrastructure grants available to govt agencies to shoot for the moon with their favorite projects. This one involved building out dozens of public safety radio sites distributed around two counties. They would be at lower elevations to provide close in coverage similar in concept to cellphone towers - multiple small footprint sites with improved signal levels to serve all public safety agencies in the region. All sites would be linked together by licensed microwave in a big ring. It was a super idea and our company was all for it. We submitted our bid, and lost. It was awarded to a company out of Florida. Okay.
A couple years go by. This company did all the civil engineering, land acquisition, tower construction, building construction, equipment purchasing, and equipment installation. They put it all together and it didn't work. They spent months, and were not making any progress. So, the agency in control of the contracts contacted us for help. They wanted another pair of eyes to look at it so to speak. We spent days looking at the plans, reviewing the bills of materials, the site plans, the tower schedules, the engineering notes, the reported issues they encountered and their remediation efforts. All very professional and well thought out.
And then I plotted the microwave dish azimuths assigned to each site on a map, and knew the answer. They aimed the dishes according to declination correction applied in Florida, not Portland OR.
They aimed all the dishes too far east by almost 20 degrees putting them several miles off course at the intended far end target. We went to a couple sites to confirm this, and found it to be true. It would have been a simple fix to realign all the dishes, but we ran into other problems. The most common was tree obstruction. Arborists had been hired to trim trees in the intended path. That work had to be redone along the correct azimuth. The second issue was the orientation on the towers. Most of the dishes were mounted so they could not swing far enough west without stopping at the tower face. The dishes had to be relocated to another leg along the corrected azimuth.
Those were not the only issue we found, but it was the most fun. I take that back. The most fun mistake was the building wooden floor joists were not strong enough to hold up the equipment inside - a fact discovered when one collapsed heaving the equipment racks out a side wall onto the ground. Oh oops. They were also a bit stingy with the amount of concrete poured for the tower legs at a couple sites. And we won't talk about the power rating of the wiring used indoors. Or the lack of grounding. Those are all great tales of glory for another day.