you must have been a surveyor with a 5 channel unit. they didn’t get all the satellites up until sometime after 1990.
I just looked at my log...1996 was the first time with the handheld Garmin. I can’t remember when we first used the Trimble unit but I remember we had to sit for 4 hours for one lousey point. Today...it’s 90 seconds....
The first unit we ever used was IIRC, a Trimble. It was huge and was flown in for the week. The case was about 2’x2’x2’ and insulated so the equipment could survive a fall from a plane.
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