The AR88 was chosen to be the main receiver for the military. There were a few different models. It was used in point to point stations like the NWT & Y radio system, Y stations and other sigint sites. The photo is of banks of AR88 sets near Vancouver used on a link to Australia. When maintained it is a nice receiver.
Performance was great and you could set the dial to a frequency and turn the set on and it would be spot on. The only kicker was the weight at just over 100 lbs. Here is a good link on the AR88 history:
https://www.radioblvd.com/ar88.htm