I forgot to mention that you can also enable Wi-Fi scan mode for the iOS AirPort Utility, as follows:

I am trying to convince them to re-do it correctly by running that separate Ethernet Cable. Instead of running a separate Ethernet Cable to that building from the house, they merely spliced into a telephone cable that was already there. Problem I am trying to solve is that I sometimes have a stronger signal in the separate building in my back yard from the Airport in the house than from the Airport in that building because of some shoddy splicing done by my Fiber Provider several years ago. That is how I came to no longer have it installed.

I did have backups of all of my data, but just reinstalled all of the software from scratch on the new Desktop & left out utilities like that until I was sure the new Desktop was operating correctly. It was on my previous Desktop that had a catastrophic failure & was replaced by Dell. I am also looking at the Nirsoft Utility 'Wireless Network Monitoring Tool' That is the information I was looking for.

Airport utility wifi scanner