I lost track of the thread but I am glad to share some of my experiences with 500 series scope. Perhaps I have owned more than necessary, but they are amazing scopes and have been wonderful additions to my lab over the past half century.
To the best of my memory I have owned the following: 532, 535, 545, 556, 575 curve tracer and most fortunately a 547 with a 1A2 plug-in.
They were all good scopes but for several reasons the 547 was hands down my favorite.
Back in 1971 or 72 I was a junior technician on my first full time job with a local company. The same month they hired me they also bought a brand new 547. It was absolutely amazing and so advanced over any other scope I had ever used. Of course, being rather new to electronics I had only used scopes made by EICO, Heathkit, RCA, Dumont and some army/navy surplus - but never anything like the 547.
The senior tech I worked for showed me a little about how to use it and he let me use for my work sometimes. Hands down it was the most amazing scope I had ever seen or used.
Well time moves on, I had gone to work for other companies and gained experience but along the way I stayed in touch with the friends I had made at my first work place. One day I learned that company was going out of business and fortune smiled upon me and I was able to buy that 547.
I used it well into the early 2000’s when I finally replaced it with 7000 series scopes as well as a TDS 620 or 640 (I’ve forgotten which).
But the 547 holds a special place in my memory because it and I were “new” at about the same time, I knew its history for more than 30 years and used it for much of that time. Additionally, it had one of the smallest spot sizes and sharpest traces of any scope I have used before or since and with its tunnel diode trigger circuit it would trigger on anything!
The 547 was, and remains, a true engineering masterpiece.
I was lucky to own one!