TELECOM Digest Editor noted in response to snipped-for-privacy@bbs.cpcn.com:
Generally, the Depression is started by be the fall of 1929 until about
1939-40. Although the big stock market crash is generally accepted to the be the start, for some people hard times started much earlier and later for others. Hard times continued until to about 1940 when defense spending perked up. There was some natural economic growth in 1939. There was a slight recovery in 1936-7, but then FDR cut the budget back and the economy fell down again.I believe Newark NJ was a major dial conversion around 1930 as was remaining manual exchanges within New York City and its immediate developed suburbs (ie Yonkers).
No 1 crossbar came out and was implemented in the 1930s.
Long distance systems continued to be modernized with improved repeaters and carrier systems. "AB" dialing for operators and other processes streamlined the process.
While work at Bell obviously slowed down since so little revenue was coming in (the stock dividends were paid out of past surplus), it didn't stop.
Someone else mentioned 25% unemployment even in 1941. That is too high. 20-%25% was about the worst the country had (except in some especially hard hit areas like the Dust Bowl), but other places weren't quite as hard hit. By 1939 it was down to about 15%. That's still very high but not quite as bad. It varied quite a bit by region and industry. There were some nasty strikes in the late 1930s that pushed up wages which allowed workers to have more money than mere sustenance.