The part about this that frightens me is using iron screws and wires to make a device that runs on house current. There was probably more to the article, but that's all I needed to see.
Poplar Mechanic's assumption, up until about ten years after the start of the computer age, was that no technology was out of the reach of the average reader. Mechanical, automotive, carpentry, (tube) electronics, everything was fair game. As opposed to today, when we buy pressed-wood bookshelves because we're afraid of saws and hammers, and have to take our cars to the garage to replace headlights. On the other hand, families in 1929 didn't have three sports per child or 300 TV channels or all the other things that absorb family's time today.