What do all the brands mentioned in the title have in common? They all offered “kit” type equipment. In other words you would build or assemble the equipment at home with a soldering pencil and hand tools. Many amplifiers, preamplifiers, tuners, etc. were built on the kitchen table as a family project. Mostly from the 1950’s and 60’s this was quite common. It was a time when people actually used their hands and brains at the same time.  A learning experience with the reward of a completed working project that you actually built.  Erector sets, electric trains, hi fi and simple electronics, etc. were all part of a normal child’s upbringing. We lived in “real” time vs. todays cyber / fantasy dream world. Kids could actually use a screwdriver and build things from reading instructions. Today it’s the smart phone. Nothing else matters or counts. Everything is done through a communications gadget in your pocket. No need for eye hand coordination unless it’s on a video game joystick. Soon there will be little use for pens/pencils. Keypads and voice recognition are the name of the game now. I must be missing something, how much fun could you really have with just a smart phone? Where are we headed? Many of todays kids can’t even screw in a light bulb(literally.) Anyway, all the brands in the title above offered some or all equipment in build it yourself kit form. Those were the days!