(Tech) Voice Frequency and ... Riverside with a minority speaking only

with a minority speaking only Spanish

coal and iron mills

but updated to show the latest additions of towns

with some minor misfolds

Image size is 16 X 11

(Tech) Voice Frequency and ... Riverside with a minority speaking only(Tech) Voice Frequency and carrier frequency transmission technology for cables, Philips, c. 1990A foundational infrastructure facet that makes the modern world possible. It's a very slow steady increase from 1912, up to the late 1950's when fully transistorized amplifiers come on the scene, but exponential growth occurs with the introduction of coaxial and fiber optics. By the 1980's capabilities begin to triple or more. It probably would be hard for