Folder BSP Categories by early Letter Code (by Doc #)


Alphanumeric codes, used from about 1930 until the early 1960s.


Folder AA-Series - Equipment Engineering
Folder B-Series - PBX Installation and Maintenance
Folder C Series - Station Installation and Maintenance
Folder G-Series - Outside Plant
Folder M-Series - Plant


pdf E34.061 I5 K1 Carrier Telephone Terminal R (96 downloads) Download (pdf, 1.16 MB)
pdf E44.062 I1 Type K Carrier Ocr R (81 downloads) Download (pdf, 2.16 MB)
pdf A217.122 I7 May58 - Selector Oper Test Using Test Set Step A218.220 A252.001 Ocr R (665 downloads) Popular Download (pdf, 407 KB)
pdf A702.625 I1 Mar63 23A Trans Measuring Set Desc E40.208 Ocr (667 downloads) Popular Download (pdf, 632 KB)
pdf AB43.910-3 AppA IA Jul50 500-Set Loop Design Tables 1950 Ocr (854 downloads) Popular Download (pdf, 640 KB)
pdf AB47.007 I1 Mar56 Bell System Capacitors (1149 downloads) Popular Download (pdf, 1.94 MB)
pdf H-85950-Office-Alarm-Circuit (1794 downloads) Popular Download (pdf, 4.47 MB)
pdf 4A 4M Xbar SC-OS-RM (1792 downloads) Popular Download (pdf, 21.69 MB)
pdf A128.819 I5 (1690 downloads) Popular Download (pdf, 381 KB)
pdf A128.820 Toll Switchboard No. 3C or 3CL, Issue 1, April 1950 - Charts (1754 downloads) Popular Download (pdf, 4.07 MB)
pdf A128.820 Toll Switchboard No. 3C or 3CL, Issue 1, April 1950 - Checking List (1697 downloads) Popular Download (pdf, 104 KB)

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