wrote
polygonum wrote

A bit early, but I'd guess that things didn't change that fast between
1902 and 1921 (and I do not know when he started his 'shop').

In electrical/electronic terms they changed hugely. Radio advanced from
coherer sets only capable of thuds to multistage reaction sets receiving
speech & music. Radio even developed enough for the first mobile phone in
1922.
http://www.ufunk.net/en/insolite/le-...-date-de-1922/

The spread of electrification, and the spread of electric motors and
heating
in a fairly wide range of appliances transformed numerous tasks.

Yeah, very striking wandering around a vintage farm machinery
field day looking at what was used to pump the whey from the
dairy to the piggery. Quite a big engine driven pump, as big as
a modern top loader washing machine. Compare that with the
much smaller electric pump that would be used today.

Industral electrification cut many costs, improving people's
standard of living. Trams went from horse pulled, spreading
horse**** everywhere they went, to clean reliable electric.
The use of electric elevators spread through medium & high
rise buildings. Electrical safety standards were transformed
over the period from suicidal to risky.

Medical uses of electricity at this time included shock coils,
electromagnets for removing metal debris from eyes, the
violet ray, and diathermy. There was also the spread of X
ray machines through hospitals in this period.

So it was a busy period of fast technological change and rollout.