To fix this Wi-Fi network, we'll need a crane

Won't somebody think of the children not being hit by a load of building materials?

On Call Delivering excellent tech support can sometimes require heavy lifting, a feat The Register celebrates each Friday with a new instalment of On Call – the reader-contributed column that shares your stories of hoisting glitchy tech back to full function.

This week, meet a reader we'll Regomize as "Harold" who told us he once worked as the IT Support Manager for a K-12 school.

"We had just put in new Wi-Fi infrastructure to support every student from year 5 to 12 using a laptop," he explained to On Call. (The range covers fourth graders in elementary school all the way up to high school kids.)

"It worked well for the first couple of weeks of term, but then we started getting reports that some of the laptops were intermittently unable to connect, or getting very slow connectivity in one area of the school," he told On Call.

A little investigation revealed that only Windows laptops experienced the problem. Harold concluded that whatever was causing the problem had something to do with the 2.4 GHz band, because Macs default to using the 5 GHz band for Wi-Fi.

Attempts to troubleshoot the situation proved futile, so Harold summoned one of the Wi-Fi vendor's technicians who duly showed up with a spectrum analyzer.

"We just had to wait for the issue to recur," Harold wrote, and thankfully "technician aura" didn't impose itself and teachers soon reported that the issue had returned.

"We looked at the spectrum analyzer and the entire 2.4GHz spectrum across all channels was blanketed by a very strong signal," Harold told On Call. "We scratched our heads trying to figure out what could cause such a loud and spectrum-wide signal."

Those ruminations were interrupted by the sound of children emerging for their lunch break, so Harold and the vendor tech moved from the IT office to a quieter balcony

From that lofty perch, Harold gazed out upon a corner of the school where a new building was under construction. "The new building was next to the area that was reporting the Wi-Fi issues. And I noticed a crane being used to deliver building materials and a crane operator with a large wireless controller strapped to his chest that he was using to control the crane."

Harold quickly joined the dots.

"The wireless remote for the crane used the entire 2.4 GHZ spectrum at maximum permitted power to ensure the controller signal was never accidentally blocked by another radio device," he told On Call. "I guessed they wanted to ensure when the controller sent a signal to the crane to stop or move, there was no chance it would be blocked or missed."

A little further observation showed that whenever a delivery of building materials arrived and the construction crew used the crane, Wi-Fi would crater.

"The solution was to temporarily move the Windows laptops to 5 GHz until the construction was finished," Harold told On Call.

What's your weirdest Wi-Fi fix? If your connection is working, click here to send On Call an email so we can share your story on a future Friday. The mailbag is a little thin at present, so don't be shy! To get your creative juices flowing, here's They Might Be Giants singing They'll Need A Crane, which in On Call's opinion is better than almost everything on the new album. Comments on that welcome! ®