[Lex Computer & Tech Group/LCTG] How to use a telephone, from 1954

[Ken Pogran]

Interesting!

The scene in the video (at 1:45) showing the moment of cutover to dial 
service clearly shows the frames of a No. 5 Crossbar office.  The Bell 
System invested heavily in No. 5 Crossbar in the early 50's as the way 
to bring dial service to its suburban territories.  Since Bell 
franchises included large metropolitan areas, Bell's earlier dial 
switchgear  (Panel, No 1 Crossbar) was oriented towards very large scale 
central office installations (think: NYC, Boston/Cambridge...). 
Step-by-step (Strowger switch) technology sufficed for small rural 
offices (and private branch exchanges—PBX's), but Bell never invested in 
developing it for larger-scale deployment like General Telephone did—the 
L.A. area being the prime example (General Telephone, and other large 
"independents", didn't have access to the Bell System's panel and 
crossbar technologies).

So in Bell territory, the in-between, suburban-sized offices remained 
manual until No. 5 Crossbar came out (with the Bell System making a huge 
push after the Korean War), aimed at offices with 10K or 20K subscriber 
lines and supporting a mix of intra-office and inter-office calls. 
(Panel and No. 1 Crossbar were designed around the assumption that, in a 
city, you were more likely to be dialing a number in a different 
exchange code than you were one in your own exchange code. In the 
suburbs, the assumption was a greater percentage of calls would be 
intra-office, and the design of No. 5 Crossbar optimized for that.)

If I'm remembering correctly,because of its size and proximity to 
Boston, Belmont was one of the first towns in New England Telephone 
territory (if not the first) to get a No. 5 Crossbar.

Ken Pogran

John Rudy via LCTG wrote on 4/9/25 8:42 AM:
>
> Bing Videos 
> <https://www.bing.com/videos/riverview/relatedvideo?q=how+to+use+a+dial+phone+1954&mid=7F1DA87AF463381268157F1DA87AF46338126815&FORM=VIRE>
>
> This is pretty amazing
>
> John Rudy
>

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