Boonton NJ was quite a center of electronics instruments manufacturing in the 1930's through post-WWII. As Rich (Dorpmuller) noted on the Antique Radio Forum some time ago:
Measurements was another company in Boonton, NJ where I grew up. Boonton used to be a hotbed of electronics and I had no trouble then getting a job.
There were: RFL, Measurements, Aircraft Radio Corp. (ARC), Ballantine and Boonton Electronics. Those just off the top of my head.
The HP Archive has an interesting article about the history of the electronic precision instruments industry in Boonton, NJ. I think it's been posted pretty recently; at least, I hadn't seen it before.
There's also an article on the history of the electronics industry in Boonton in the Boonton Radio Corporation journal "The Notebook", issue number 9 pages 7-8.
Finally, there's an interesting oral interview with Jerry Minter, one of the founders of Measurements Corporation. It’s on the very interesting "Engineering and Technology History Wiki” web-site.