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

CLICK HERE FOR THE LIST VIEW.

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

Categories

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

Documents

Title	Date	Download
pdf 4A 4M Xbar SC-OS-RM (4662 downloads) Popular	01 Feb 2010	Download (pdf, 21.69 MB)
pdf A128.819 I5 (4314 downloads) Popular	01 Feb 2010	Download (pdf, 381 KB)
pdf A128.820 Toll Switchboard No. 3C or 3CL, Issue 1, April 1950 - Charts (4804 downloads) Popular	31 Jan 2010	Download (pdf, 4.07 MB)
pdf A128.820 Toll Switchboard No. 3C or 3CL, Issue 1, April 1950 - Checking List (4120 downloads) Popular	31 Jan 2010	Download (pdf, 104 KB)
pdf A199.850 iA Apr61 - CO Maintenance Telephone Directory (2965 downloads) Popular	21 Mar 2019	Download (pdf, 6.50 MB)
pdf A217.122 I7 May58 - Selector Oper Test Using Test Set Step A218.220 A252.001 Ocr R (3018 downloads) Popular	24 Jan 2014	Download (pdf, 407 KB)
pdf A438.675 i2D Apr40 - Switches 300 301 302 303-types (2244 downloads) Popular	21 Mar 2019	Download (pdf, 17.66 MB)
pdf A702.625 I1 Mar63 23A Trans Measuring Set Desc E40.208 Ocr (3168 downloads) Popular	14 Jan 2014	Download (pdf, 632 KB)
pdf A837.001 i1 Jun 1932 General Description No. 12 Switchboard (1017 downloads) Popular	08 Dec 2021	Download (pdf, 3.35 MB)
pdf A837.002 i1 Apr 1936 General Description 640-line and 1440-line no. 12 Switchboard (1144 downloads) Popular	08 Dec 2021	Download (pdf, 4.03 MB)
pdf AB43.910-3 AppA IA Jul50 500-Set Loop Design Tables 1950 Ocr (3099 downloads) Popular	19 Sep 2013	Download (pdf, 640 KB)
pdf AB46.372A i1 Sep50 - 372A Cold Cathode Tube (2105 downloads) Popular	02 Feb 2019	Download (pdf, 78 KB)
pdf AB46.425A i4 Jun62 - 425A Electron Tube (1950 downloads) Popular	02 Feb 2019	Download (pdf, 117 KB)
pdf AB46.426A i4 Jan62 - 426A Electron Tube (2258 downloads) Popular	02 Feb 2019	Download (pdf, 102 KB)
pdf AB47.007 I1 Mar56 Bell System Capacitors (4340 downloads) Popular	04 Aug 2013	Download (pdf, 3.27 MB)
pdf E34.061 I5 K1 Carrier Telephone Terminal R (2651 downloads) Popular	10 Feb 2015	Download (pdf, 1.16 MB)
pdf E44.062 I1 Type K Carrier Ocr R (2542 downloads) Popular	10 Feb 2015	Download (pdf, 2.16 MB)
pdf H-85950-Office-Alarm-Circuit (4364 downloads) Popular	24 Sep 2010	Download (pdf, 4.47 MB)
pdf H-series "Buildings" BSP Collection 1932-60 (1600 downloads) Popular	30 Mar 2021	Download (pdf, 21.54 MB)

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Recent Contributors

Thanks for new documents from Jim Hurtle, Ed Palazzo, Paul Fassbender, Bruce Patterson, Remco Enthoven, Jon Kolger, Paul Ivester, Len Hicken, Fred Haynes, Kurt Rudolph, Wade ("Kellogg KITT"), the Connections Museum, Rick Walsh, Jeff Lamb, Jeremy Walters, Alan David, Dennis Hock, and Tim Griffin.

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