"Well-informed people know it is impossible to transmit the voice over wires. Even if it were, it would be of no practical value." -- Boston Post 1865

I worked at the Norfolk & Carolina Telephone & Telegraph Companies from 1970 to 1980.

You can call me on anonymous SIP. Ask. IRC channel #voipcoop for more. Or you can call me on C*net 1-KODIAK-1. http://www.ckts.info

Telephone Technical Reference

• Western Electric US Air Force collection from White Alice Communications System (WACS) June 2009
  • Type L Group and Supergroup equipment J-68774 T.O. 31W1-4-56-1 (black binder)
  • 43A1 Carrier Telegraph System, J-70112, CE-44, T.O. 31W1-4-62-1, 30 April 1963 (black binder)
  • 72A Frequency Meter J64072A, TE-132, May 1961, SD-59373-01 + 20 pages (black binder)
  • Ringing Supply J-86212K, CE-24, T.O. 31R2-4-150-1, 15 Feb 1963 (black binder)
  • 425A Rectifier Type Power Plants CE-163, July 1961, 130 volts, 20 amps. (black binder)
  • Test Set 96A, Test Set F-50469, Wheatstone Bridge KS-5588, FSN 6625-893-6224, TE-16, December 1961 (black binder)
  • Test Oscillator Model 650A, Hewlett-Packard, T.O. 33A1-8-130-1,2,4, TE-104, 15 Nov 1957 (black binder)
  • FM Terminal Receiver, J-68336G, CE-72-2, January 1962, SD-59363-01 (black binder)
  • [No. 9 Telegraph Testboard J-63511AB, CE-48] ITEM NOT IN JACKET - this jacket contains White Alice operating instructions (black binder)
  • Interrupter Supply and Distribution Circuit, 30, 60 or 120 IPM, J86212S, J99235, CE-205, April 1963 (black binder)
  • No. 9 Telegraph Testboard J-63511AB, CE-48, T.O. 31W1-4-52-1, 30 June 1963 (black binder)
  • AC Relay and Signalling Test Set J68602AJ, TE-90, December 1961 (black binder)
  • 53A Mobile Oscillator J64053A, TE-55, November 1961 (black binder)
  • TD-2 Radio System, CE-73, July 1962, 93 pages (many are foldouts) (black binder)
  • Varistor Test Set KS-12054, TE-6, Simpson Electric Co. (black binder)
  • Type K Group Equip[ment J-68784A, J-68784C, CE-39 (black binder)
  • Type A4-12 Channel Bank J-68834A, J-68834B, J-68834C, CE-37, 15 June 1963, T.O. 31R2-4-152-1 (black binder)
  • ABC of the Telephone by Frank E. Lee 1944+ Vol 1-2-3. (three white booklets)
  • RCA Service Company White Alice System advanced training: TD-2 Microwave, REL Tropo, Carrier, Telephone, Telegraph, Circuit Layout, Power, Outside Plant, Test Equipment, Emergency Service Restoral. (no jacket)
  • AT&T Microwave Exposure Limits, October 24, 1957 1S3.10-1 (no jacket, 6 pages)
  • No jacket, several documents in one sheath
    -Instructions for reading Western Electric Company's Wiring Diagrams, 26 sheets
    -General Info. on Prints & Drawings WHITE ALICE, 19 pages
    -Test Equipment, 14 pages
    -Trouble Analysis
    -General Introduction to Forward Propogation Tropospheric Scatter (FPTS), 10 pages
    -Carrier Course - General Circuit Description, 12 pages
    -The TD-2 Radio Relay System, 5 pages
    -Over-all TD-2 Radio System, 4 pages
    -FM terminal transmiter and receiver
    -Handbook 9, Western Electric Company, Inc., Installation Organization,
    -Removing and Grounding Shields, Forming, Splicing and Terminating Shielded Wiring and Coaxial Cable and Twin-Conductor Shielded office cable. (5-5-55, very poor thermal copy)
  • OJT White Alice instructions, Advanced Training Course, TD2, REL, CXR, 18-B board, No. 9 Telegraph Board, Circuit Order, CLR cards, Batteries, Outside PlantTest Eq. (redish brown binder)
• Cable color code or in plain black and white.
• Switchboard lamps voltages and currents, WeCo only.
• Type 12 and 13 Resistance Lamps
• Type 120 Repeating Coils and No. 251 Retard coils.
• From 1938 edition of AT&T Principles...
  • Table V Approximate Inductance Values for Windings of Various Electrical Apparatus. Includes Receivers 144, 525, 528; Retardation Coils 5-U, 5-AA, 77-A, 12-A, 44-D, 47-B, 57-B, 82-H, 182-B; and AC Relays 172-B, 196-A, 218-B and J-1.
  • Table IX Phantom Repeating Coils. Mounted in pairs on a single base. Types 62, 75, 85 and 93.
  • Table XVI Electrical Constants for Various Types of Vacuum Tubes. Types 101-D, 101-F, 102-D, 102-G, 102-F, 104-D, 205-D, 205-E, 215-A, 245-A, 246-A, 259-A, 281-A, 285-A, 310-A, 311-A, 328-A.
• BSP 402-421-100 September 1975, Microwave Antennas, KS-15676 Horn-Reflector Antenna, Description
• From 1953 edition of AT&T Principles...
  • Transformers, Phantom Circuits and Repeat Coils text, drawings, and specs on type 62 and type 93 coils.
• Basic Circuits by Automatic Electric. Booklet 4 x 9 inches with 39 schematics. Dated 1967.
• Engineering Considerations for Microwave Communication Systems, 158 pages and many foldout charts. 1970 edition 4th printing 1975.
• Military
  • German army field switchboard, schematic (Unit is in our museum)
  • EE-8 field phones
  • EE-91 Fire control phones
  • TM 11-330 Switchboards BD-71 and BD-72. 6 to 12 line field switchboard for EE-8 type field phones.
  • TM 11-333 Telephones EE-8, EE-8A and EE-8B. Local battery magneto field phone.
  • TM 11-2052 Switchboards BD-95 and BD-105. 12 to 20 lines. For local battery field phones such as EE-8 series. Has schematic of EE-91, used for operator.
• Instructions, circuit description and schematic LORAIN Model F4A and 4871-307 tone generator.
• ITT 96101-2 key system power supply schematic
• Type 10A2 Six-Line Key Telephone system H-850346-B SA-692-1 Iss 6, 7 pages
• Small pocket size 1A or 1A1 circuits: 25B, 26B, 29A, 6C, 16A, 57A, 207A, 208A.
• 1A1 System connection data 202A 202B 209A C71.340 Iss 3, April 1959
• 1A1 System connection data 202A 202B 212A C71.341.1 Iss 2, April 1959
• 1A1 System connection data 16A 211A C71.341.2 Iss 2, Jan 1959
• 1A1 System connection data 230A 202C C71.341.3 Iss 1, Sept 1959
• 1A1 System connection data 207A 207B 207C 208A 209A 212A C71.342.1 Iss 3, June 1959 Page 1, Page 2.
• 1A1 System connection data 207A 207B 207C C71.342.2 Iss 3, June 1959
• K307A Dial Intercom KTU KSP307-00A Iss 5, Oct 78
• Valcom V-1109 9-zone talkback page control unit (Mine is available on voip - ask)
• Loudspeakers
  • ITT K107A Loudspeaker Iss 7 Jan 80 88279-1, hookup & schematic
  • 106 type loudspeaker BSP 463-220-100 Iss 4 Apr 1969, includes schematic, 10 pages
    • Left half of schematic
    • Right half of schematic
    • Hookup diagram
  • WECO 100E Loud Speaker Set Bulletin 839 (original softcover) Schematic.
  • 100-Type loudspeaker sets, BSP 024-101-100 Iss 1 Dec 1956, Schematics of A-F, good copy
    • Text of BSP
    • Figure 3 and 4, ABCD schematics
    • Figure 5 and 6, EF schematics
• 11-pin plug-in audio units
  • Altec 449B transistor amplifier, text only.
  • Altec 456B transistor amplifier schematic and text.
  • Altec 469A transistor amplifier schematic and text.
  • Altec 41499A general purpose relay sketch
  • Lorain 460C compressor amplifier simplified schematic and text.
• Misc loose schematics of phones: (*2-sided sheets that came in the box with the phone)
  • *ITT Type 510 - - ( - - ) 30 - and Type 510 - - ( - - ) 36 - desk telephones
  • Stromberg 2500
  • 2500 schematic North Supply Premier
  • K-2500 & K-3554 modular, dwg 186123-101
  • Unk brand 2502
  • Stromberg-Carlson 1248 & 1258 magneto desk set. Stromberg-Carlson 1268 desk set box, magneto used with 1244 desk set
  • Stromberg-Carlson S-C 1654 B Telephone, 206074-700 Iss 7
  • *AE Type 80 rotary (PC net) standard & superimposed, SA-911-1 Iss 5, Page 1, Page 1 inset, Page 2, for key system use.
  • *AE Type 90M rotary (PC net) standard & superimposed, SA-912 Iss 4
  • *AE Type 186 with dial, SA-938-1 Iss 4
  • *AE Type 187 with dial, SA-939-1 Iss 4
  • American Telecommunications Corp Candlestick Telephone Mod 4100, Dwg WD-4100 7-23-71.
  • ITT K200/K254/K2200/K2254 telephones, 1-70 (poor copy)
  • Northern Electric Co Ltd/Northern Telecom Inc connection info chart for NE-500, 554, 2500 and 2554
• Notes regarding Lenkurt carrier and related sketches
  • Lenkurt and WeCo carrier
  • WeCo H1 with phantom circuit
  • WeCo H1 levels
  • Lenkurt 333A dial panel schematic
  • Lenkurt 521B power supply
  • Lenkurt 54x series filters
  • Lenkurt 333 dial panel with WeCo H1 carrier
  • Frequencies used for 33, 45A and other carriers from page 74 CARRIER AND RADIO ARTICLES SELECTED FROM THE LENKURT DEMODULATOR, 1959
  • Filter arrangement and frequencies for 33 and 45A carrier from page 111 CARRIER AND RADIO ARTICLES SELECTED FROM THE LENKURT DEMODULATOR, 1959
  • Frequency allocations of several typical cable carrier systems. from page 65 SELECTED ARTICLES FROM THE LENKURT DEMODULATOR, VOLUME 1, 1971
• 1A2 Technical Notes
• Key Telephone Systems Working Practices Southwestern Bell June 1969 It's about 1.75 inches thick, 8.25x11 with orange cover.
• 1A2 notebook, schematics only unless otherwise noted, # no schematic
  • SC 1800/1810 2800/2810 series 5-line telephones
  • ITT 1A2 Telephone Systems Guide, 27 pages glossy
  • K-20C & K-254()-20,-27 & -28 type modular telephone circuit
  • ITT 510--(--)30- and 510--(--)36- desk telephones
  • Comdial 6-button wall phones, 703084-100 iss 9
  • K-2500 & K-3554 () 20, -20T, -24, -27, -28, -44 modular telephones
  • Stromberg 2500
  • Stromberg 2502
  • 2554 North Supply Premier
  • 2564 () 40, 41 telephone, page 2
  • 2575
  • 2830 () 42, 46 183157-101 iss 6
  • 2842CL (BA/LR) 42M 186185-101 iss 1
  • 2844CL (BA/LR)39M 188577-101 iss 4
  • 3528D Comdial Maxcom 6-button telephone 703802-500 iss 3
  • 2854 () 42 183514-101 iss 8
  • 2500 TAP models 20F, 27F, 27P, American GST Inc.
  • Teledial TD-2010-1 line powered tone memory dialer #
  • Teledial TD-200SR toll restricted tone dialer #
  • San/Bar SB700A and SB701A touch pad dialer, 10 pages #
  • Teledial TD-5040 #
  • Teledial TD-102SN-B-2 tone/pulse single number dialer #
    instructions and picture of back showing 3-volt battery hookup.
  • Melco KC-19 intercom KTU, tone/rotary #
  • San/Bar 6609B-101 tone converter, with MT8820 I.C.
  • San/Bar schematic, 20 station intercom, rotary
  • BSP C71.342.1 iss 3 June 1959, 1A1 dial intercom circuits
  • SD-69288-01-C34 207C KTU intercom selector circuit
  • Tone Commander HF-1910 intercom, catalog sheet only
  • AE WX-302 intercom, installation only WW-10757-23 7/22/77
  • AE H-889748-1 and -5 electronic intercom for 10A2, SA-975 iss 2, 22 pages
  • K307A rotary intercom KSP307A-00A iss 5 Oct 78, including info on Tel-Touch adapter 182666-101, uses cards K-160B and K-160C
  • AE WA-1400D line card schematic
  • K400D line card, 6 pages, KSP 400-00D-101 Iss 1 Jan 75
  • K400E line card, 4 pages, KSP 400-00E iss 3 Aug 77 1 - 2 - 3 - 4
  • San/Bar 4200A line card with music-on-hold
  • K-259 (B) panel, (two card adapter) two 400 type card sockets to terminals
  • K415A KTU automatic ring-down tie-line, KSP 415-00A iss 1,page 2
  • San/Bar SB6640B 8-line key system, 8 pages, Section 6640-000 Apr 81
  • K501 Key Service Unit Terminal Connections, 1 page
  • K501A series KSU KSP501-00A iss 4 Oct 79, 23 pages
  • Teletrend SAU9640 secretarial answering unit, 4 pages
• BSP 518-215-125 iss 2 Aug 70 400 series KTU indentification, 47 pages, contains functional schematics of the following KTU: (back of white 1A2 binder)
  • 400D CO or PBX line circuit
  • 400E CO or PBX line circuit
  • 401A manual intercom
  • 402A diode matrix
  • 404A diode matrix
  • 405A multiline exclusion
  • 407B 10-code selector
  • 412A auxiliary relay
  • 413A auxiliary ringup
  • 414A manual signaling, ringdown tie line
  • 415A automatic, DC signalling tie line
  • 416A station line circuit
  • 417A add-on conference
  • 418A short range, DC signaling, tie line
  • 419A automatic signaling, ringdown tie line
  • 420A long line
  • 421A power failure transfer
  • 422A/B station busy selector
  • 423A dial tone, busy tone and audible ringback tone
  • 424A 19-code selector
  • 425A/B flashing lamp
  • 426A amplifier, band separation and limiter (touch tone deoder)
  • 427A/B frequency recognition and translation (touch tone deoder)
  • 428A multiline exclusion
  • 429A detector circuit, part of supplimentary hold circuit
  • 430A flutter generator and limiter, part of supplimentary hold
• Miscellaneous special services (3-ring binder)
  • Pulsecom DC to DC converter Model 5862-1L2 & L3, Iss 2, Feb 1978
  • Northern Telecom
    • VF-300 echo supressor QVF34K 11/24/1980, 23 pages xerox
    • VF-300 compandor QVF56A and D, 9/21/1979, 16 pages xerox
  • Transcom
    • Noise Supression circuits, May 1978, 3 pages
    • TPI Tip Party Identifier, August 1983, 6 pages
    • Transcom TE-FA30 fuse & alarm panel, 2 pages
  • Westell 4468 DTMF to Dial Pulse Converter, 5 pages
  • GTE
    • 4900 pad/transformer with sealing current, July 14 1981, 6 pages
    • 4100 4-wire prescription line amplifier, May 1981, 11 pages
  • Elgin
    • SM15704A 10 watt/20Hz switchmode ringing generator, Sept 1985, page 1, page 2
    • SM15104A 75 watt/48 VDC switchmode power supply, Sept 1985, 2 pages
    • 1986 telephone power selection guide, 17 pages
  • Dantel
    • 90951 loopback module, 13 pages
    • 48020 frequency selectable ringing generator, Jan 1982, specs only, 2 pages
  • Tellabs
    • 260 signalling and terminating system, Oct 1979, 14 pages xerox
    • 261 signalling and termination system, April 1978, 20 pages
    • 269S signalling and termination system, March 1980, 11 pages
    • 310 datavoice system, 2 pages specs only
    • 1911 and 1912 apparatus cases, 1997, 8 pages
    • 1914, 1914 and 1914PR Apparatus Cases, 1983, 6 pages
    • 4001A line amplifier, Dec 1977, 8 pages
    • 4101 echo suppressor, Mat 1976, 8 pages
    • 4201 and 4203 terminating sets, March 1979, 6 pages
    • 4412A data station termination, Jan 1977, 10 pages
    • 4424 and 425 wideband repeat coils, Aug 1978, 4 pages
    • 6101 SF transceiver, 5 Sept 1976, 6 pages
    • 6101 SF transceiver, 3 Sept 1976, 8 pages
    • 6103 signalling converter, FX station, 11 pages schematic
    • 6104 signalling converter, FX office, April 1976, 8 pages
    • 6923 2-wire FXS SF signalling set, Sept 1979, 15 pages
    • 6924 2-wire FXO SF signalling set, Feb 1980, 15 pages
    • 7201 2-wire switched gain repeater module, Nov 1981, 8 pages
    • 8102 Ringing Generator (24-48 VDC input) 3 Mar 1981, 5 pages
    • 9001 (24v) and 9002 (48v) Relay Modules (four 4-pole relays), 3 Aug 1975, 4 pages
    • radio to carrier FX system, 1 drawing 2/25/80 (uses modules 4001, 6101, 6102, 4401, 9131, 9001, 6103, 82-4201/3)
  • Proctor complete practices and schematics
    • 65052 sleeve control, pages 1 2 3 4 5 6
    • 71045 one way trunk circuit
    • 71911 emergency service bureau trunk
    • 72076 trunk circuit, two way loop to E&M
  • Cook 1850L2 trunk circuit, two way loop to E&M
• Wescom, Wescom/Rockwell (red 3-ring binder)
  • 401 dual line amplifier, iss 4 Dec 1071, 8 pages xerox
  • 404 dual station circuit module, iss 2 May 1971, 5 pages xerox
  • 410 transfer relay module iss, 1 Mar 1978, 11 pages original
  • 412A pad/transformer, schematic only, 1 page xerox (measured frequency response curve)
  • 416 4w/6w conference bridge, iss 1 Feb 1972, 5 pages original
  • 441 and 442 terminating sets, iss 1 April 1971, 12 pages xerox
  • 443 terminating set, iss 2 Oct 1972, 10 pages xerox
  • 452-FWA, (also 451) E&M inband signalling system, iss 2 Feb 1973, 12 pages xerox
  • 690A/B battery & filter distribution shelf, iss 2 May 1972, 6 pages xerox
  • 730 dual repeat coil, iss 1 Sep 1972, 6 pages original
  • 840 48v/841 24v regulated power supply, iss 4 Mar 1978, 5 pages original, no schematic
  • 851 ringing generator, iss 2 May 1971, 5 pages original
  • 4124 4-wire pad/transformer/loopback, 1 page schematic xerox
  • 7310 High-sensivity relay module, iss 1 March 1971, 6 pages original
  • 7311 & 7312 DX1/DX2 signalling modules, iss 3 Apr 1977 with addendum B, 15 pages original
  • 7382 loop extender module, iss 1 Dec 1972, 10 pages original
  • 7382-10 & 7386-10 loop extender, iss 2 Oct 1977, 14 pages original
  • 7305-30, 2-wire loop signalling repeater iss 1 Oct 1981 with supplement A, 12 pages original
  • 363 D4 terminal product data sheet only, 3 pages original
  • 360 channel bank applications manual, 30 pages original
  • D4 channel bank, glossy brochure, 10 pages original
  • 70A 4-wire terminating assembly, iss 2 June 1978, 1 page block diagram xerox
  • 707 E1S E1S/A 2600 Hz inband signaling system, iss 2 Feb 1969, 8 pages xerox
  • 708 E2L E2L/A 2600 Hz inband signaling system, iss 2 May 1968, 10 pages xerox
  • 708 E2L E2L/A 2600 Hz inband signaling system, iss 1 May 1970, 7 pages xerox
  • 709 signalling system, July 1969, 2 pages schematic only xerox
  • 711 term set, hand drawn schematic, 1 page
  • 711 line amplifier, iss 1 Dec 1968, 9 pages xerox
  • 702-E4B inband signalling system, iss 1 Sep 1966, 10 pages xerox (schematic original)
• General System Practices (telephone instruments)
  • 473-422-201 980 Styline Touch Calling, iss 1 Nov 1970, 9 pages
  • 473-215-200 80 with rotary dial, all variations, iss 3, Nov 1970, 25 pages
    • addemdum 1, September 1972, 3 pages
  • 473-220-201 182A rotary dial, issue 2, Dec 1969, 9 pages
    • addendum issue 2, Jan 1971, 5 pages
  • 473-220-202 182A touch calling, issue 2, Dec 1969, 13 pages
    • addendum issue 1, May 1970, 1 page
  • 473-300-200 90M rotary dial wall, iss 4, Dec 1969, 17 pages
    • addendum issue 2, Mar 1972, 1 page
  • 473-301-200 183 rotary dial spacesaver, iss 1, June 1965, 8 pages
  • 473-310-200 192A rotary compact wall, iss 3, Oct 1970, 10 pages
  • 473-310-201 192A touch call compact wall, iss 2, Mar 1970, 14 pages
    • addendum issue 1, May 1970, 2 pages
  • 473-410-200 880 rotary speakerphone, iss 3, Dec 1969, 19 pages
    • addendum issue 1, May 1970, 2 pages and 2 attachments
  • 473-410-201 880B touch call speakerphone, iss 2, May 1972, 13 pages
    • addendum issue 1, May 1973, 1 page and 1 attachment
  • 473-422-200 980 rotary Styleline, iss 3, Sep 1972, 11 pages
  • 473-506-200 890A rotary Call Commander key, iss 1, May 1966, 13 pages
    • addendum issue 1, Nov 1972, 1 page
  • 473-506-201 860B key, iss 1, Jul 1969, 22 pages
    • addendum issue 2, Nov 1972, 1 page
  • 473-512-200 186 key, iss 2, Jun 1972, 15 pages
    • addendum issue 1, Dec 1972, 1 page
  • 473-513-200 186 key, iss 2, Jun 1971, 21 pages
    • addendum issue 1, Jul 1972, 1 page
• SD-69288-01-A1, Station Systems, Key Telephone Units Circuits, Panel Mounted Units, 98 sheets. (1A1 key tel systems) issue 16B 10/28/66

  Some of these are available here.

  • 4 pages, sheet index
  • SD-69288-01-C1, 201B KTU, fuse unit
  • SD-69288-01-C2, 202B KTU, central office or PBX line circuit
  • SD-69288-01-C3, 203A KTU, automatic tie line circuit
  • SD-69288-01-C4, 204A KTU, ringdown tie line circuit
  • SD-69288-01-C5, 205A KTU, station line circuit
  • SD-69288-01-C6, 207B KTU, selector circuit
  • SD-69288-01-C7, 208A KTU, signalling unit for flashing line lamps
  • SD-69288-01-C8, 209A KTU, lamp flashing and time-out circuit
  • SD-69288-01-C9, 210A KTU, wink circuit
  • SD-69288-01-C10, 211A KTU, intercommunicating line circuit, ringing lamp circuit, noise supression circuit and audible signal control circuit
  • SD-69288-01-C11, 212A KTU, central office or PBX line circuit; lamp flashing and incoming signal time-out circuit
  • SD-69288-01-C12, 213A KTU, joint use line circuit
  • SD-69288-01-C13, 214A KTU, station signalling circuit, single talking link circuit
  • SD-69288-01-C14, 214B KTU, single talking link circuit
  • SD-69288-01-C15, 214B KTU, station signalling circuit
  • SD-69288-01-C16, 215A KTU, station signalling circuit
  • SD-69288-01-C17, 216A KTU, transfer circuit
  • SD-69288-01-C18, 217A KTU, preset conference circuit
  • SD-69288-01-C19, 218A KTU, two and four wire private line,station circuit
  • SD-69288-01-C20, 219A KTU, two and four wire private line, line circuit
  • SD-69288-01-C21, 220A KTU, two and four wire private line, ringing relay or power supply circuit
  • SD-69288-01-C22, 221A KTU, executive calling control and no-such-number circuit
  • SD-69288-01-C23, 222A KTU, two talking link circuit
  • SD-69288-01-C24, 222A KTU, station signalling circuit, two talking links
  • SD-69288-01-C25, 223A KTU, station signalling circuit, two talking links
  • SD-69288-01-C26, 224A KTU, busy signal and camp-on control circuit
  • SD-69288-01-C27, 225A KTU, long line circuit
  • SD-69288-01-C28, 226A KTU, inward conference control circuit
  • SD-69288-01-C29, 227A KTU, common audible control circuit
  • SD-69288-01-C30, 228A KTU, blank unit with 40 screw terminal punchings
  • SD-69288-01-C31, 229A KTU, auxiliary relay unit
  • SD-69288-01-C32, 202C KTU, CO or PBX line circuit
  • SD-69288-01-C33, 230A KTU, CO or PBX line circuit
  • SD-69288-01-C34, 207C KTU, selector circuit (dial intercom)
  • SD-69288-01-C35, 231A KTU, line and control ckt
  • SD-69288-01-C36, 233A KTU, CO or PBX line circuit, 10 circuits
  • SD-69288-01-C37, 213B KTU, joint use line circuit
  • SD-69288-01-C38, 232A KTU, electro-mechanical flash, wink, ring and timeout circuit (with KS-15900,L1 interrupter unit)
  • SD-69288-01-C39, 234A KTU, selector & transfer single link circuit
  • SD-69288-01-C40, 234A KTU, selector & transfer single link circuit
  • SD-69288-01-C41, 235A KTU, station line concentrator for 18 lines
  • SD-69288-01-C42, 236A KTU, station line concentrator for 30 lines
  • SD-69288-01-C43, 226B KTU, inward conference control ckt
  • SD-69288-01-C44, 202D KTU, CO or PBX line circuit
  • SD-69288-01-C45, 230B KTU, CO or PBX line circuit (4 ckts)
  • SD-69288-01-C46, 239A KTU, CO or PBX line circuit (11 ckts)
  • SD-69288-01-C47, 238A KTU, CO or PBX line circuit (9 ckts)
  • SD-69288-01-C48, 237A KTU, bridging circuit
  • SD-69288-01-C49, 232B KTU, electro-mechanical flash, wink, ring and timeout circuit (with KS-15900,L1 interrupter unit)
  • SD-69288-01-C50, 229B KTU, auxiliary relay unit
  • SD-69288-01-C51, 240A KTU, line transfer circuit
  • SD-69288-01-C52, 241A KTU, auxiliary line transfer circuit
  • SD-69288-01-C53, 242A KTU, 4-wire line circuit (touch tone)
  • SD-69288-01-C54, 243A KTU, 4-wire line circuit (rotary dial)
  • SD-69288-01-C55, 201C KTU, fuse unit
  • SD-69288-01-C56, 249A KTU, CO or line circuit
  • SD-69288-01-C57, 250A KTU, add-on circuit
  • SD-69288-01-C58, 240B KTU, line transfer circuit
  • SD-69288-01-C59, 244A KTU, line transfer circuit
  • SD-69288-01-C60, 245A KTU, attenuator pad
  • SD-69288-01-C61, 247A KTU, touch-tone adapter, receiver circuit
  • SD-69288-01-C62, 247A KTU, touch-tone adapter, selector circuit
  • SD-69288-01-C63, 248A KTU, 4-wire private line station circuit
  • SD-69288-01-C64, 251A KTU, ringup relay circuit
  • SD-69288-01-C65, 252A KTU, tone cutoff ckt
  • SD-69288-01-C66, 253A KTU, station selection circuit
  • SD-69288-01-C67, 254A KTU, station selection circuit & amplifier ckt
  • SD-69288-01-C68, 255A KTU, 4-wire line circuit with E&M lead signalling
  • SD-69288-01-C69, 256A KTU, active side-tone network for 4-wire links
  • SD-69288-01-C70, 258A KTU, line transfer circuit
  • SD-69288-01-C71, 259A KTU, adapter unit
  • SD-69288-01-C72, 260A KTU, multi-line exclusion ckt
  • SD-69288-01-C73, 216B KTU, transfer circuit
  • SD-69288-01-C74, 237B KTU, bridging ckt
  • SD-69288-01-C75, 259B KTU, adapter unit
  • SD-69288-01-C76, 217B KTU, preset conference ckt and conference time-out ckt
  • SD-69288-01-C76, 224B KTU, busy signal and camp-on control ckt
  • SD-69288-01-C77, 243B KTU, 4-wire line ckt (rotary dial)
  • SD-69288-01-C77, 262A KTU, transfer ckt
  • SD-69288-01-C78, 248B KTU, 4-wire private line station ckt
  • SD-69288-01-C78, 252B KTU, tone cutoff & line current limiting ckts
  • SD-69288-01-C79, 253B KTU, station selector ckt (for intercom 2A SD-69480-01)
  • SD-69288-01-C80, 227B KTU, common audible control ckt
  • SD-69288-01-C80, 243C KTU, 4-wire line ckt (rotary dial)
  • SD-69288-01-C81, 263A KTU, common visual and audible signal control ckt
  • SD-69288-01-C81, 265A KTU, blank unit with relay mountings
  • SD-69288-01-C82, 247B KTU, touch-tone adapter ckt for use with 207 selector
  • SD-69288-01-C83, 247B KTU, touch-tone adapter ckt for use with 407A selector
  • SD-69288-01-C84, 247B KTU, sub ckts, part of touch-tone adapter
  • SD-69288-01-C85, 247B KTU, sub ckts, part of touch-tone adapter
  • SD-69288-01-C86, 259C KTU, adapter unit
  • SD-69288-01-C87, 253B KTU, station line concentrator for 18 lines
  • SD-69288-01-C88, 236B KTU, station line concentrator for 30 lines
  • 12 pages of relay adjustments
• GTE Key Telephone System Handbook. Index
  Note: This book is printed on very thin newsprint which has yellowed a little. It is an inch and a half thick. The pages are not numbered but there are many hundreds. Each section listed in this index consists of many pages with text, tables and diagrams. Some of them have been scanned and are here.
  • Selector Circuit Type 16A; H-883002-70, H-85973-1 from Section 484-400-400 page 16 of 20. Circuit explanation from Section 484-400-400 page 5 of 20.
  • Type 80 telephone modified for key system, with potted self-compensating transmission network D-38384-A.

Main Index

• Coast Guard Landline Communications 1873 Through 1974
• Bell system documentation in BSP order. See for index.
• Sam Etler scans of documentation - many BSPs
• Bell System Technical Journal 1922-1983 with search
• Steve Hilsz vast telephone resources and dial repairs(Salome AZ)
• Central Office Pictures A Tribute to Telephone Central Offices and the AT&T Long Lines Microwave Network of California and the Nation
• C*Net telephone collector's VOIP network
• The Microwave Radio and Coaxial Cable Networks of the Bell System by Albert LaFrance
  • Principles of Electricity Applied to Telephone and Telegraph 1953 edition, complete, 35 megabytes
  • AT&T Long Lines Technology and Equipment Analog Frequency Division Multiplexing by Albert LaFrance
• The Bell System's Microwave Radio and Coaxial Cable Networks backup site for above link
• Kellogg Switchboard and Supply Co and ITT Catalogs, brochures, bulletins, wiring diagrams and other print material
  • Kellogg Pole Changer vibrator ringing machine from 1918. With schematic.
• Teletype
• Manuals including Teletype (enter TELETYPE in the search)
• Some discusion on how a phone works with a simple dial phone schematic (500 phone)
• Telephone Collectors International, Singing Wires newsletter and more
  • Switcher's Quarterly magazine and The Bruce Crawford Memorial Documentation Library
  • Library of schematics.
• Dave's Antique Telephone Links to schematics and more
  • Number Cards
• Radio interference filters for telephones
• Cambridge Electronics Laboratories PC mount ringing generator and booklet "Old Telephones and How to Repair Them"
  • Alternate link to "Old Telephones and How to Repair Them"
• Mike Sandman's new phone supplies and tools, in Chicago.
• 1A2 general discussion
• How to deal with the not-so-mellow-yellow of old computers and consoles
• Phoneco old phones. Wisconsin.
• Restored vintage phones
• Play things of the past Medina Ohio.
• New Parts for Old Telephones
• Bell System Memorial by David Massey.
• Bell System Memorial "One Policy, One System, Universal Service." The Bell System before 1984.
• Antique Telephone Collectors Association by Chuck Eby. I'm member No. 3541.
• Telephone schematics and more VERY EXTENSIVE SITE
• Modular jack wiring, not everything but a good start.
• Intercom unit used at my house.
• Strowger mailing list, somewhat Great Britain oriented but covers the world too.
• Sam's Telecomms History Links Page
• Museum of Communications in Seattle formerly the Vintage Telephone Equipment Museum
  • Museum official page, new July 2002
  • OLD Museum official page This web site doesn't do justice to the museum. The museum is absolutely fantastic. Maybe better than the Smithsonian.
  • Tom Farley's pages on this museum.
• Secret telephone systems in the D.C. area
• Herb Yeates's pages Industrial Archeology
• The Cedar Knoll Telephone & Telegraph Company Paul Wills
• Porthcurno centre for the history of international telegraph communications. By Cable & Wireless.

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• Doing your own telephone wiring by Sean Kurisuto
• House of Telephones cloth cords and repro parts for very old phones.
• OldPhoneWorks very expensive antique phones and parts, good reproduction plastic parts
• ATCS Schematics Older phones: Antique Telephone Collectors.
• Paul F. Old Telephones as entertainment.
• Antique Telephone Collectors Association This is the mother lode of telephone information on the web!
• Antigue Telephone History Chuck Eby
• VTS Industrial Company Antique telephone repair and parts. Steve Hilsz, Salome AZ. EE-8 handset cords. Alternate site
• Kellogg Telephone Page Reference info and documentation for Kellogg phones.
• Peter Walker's Telephone Site Very well organised frame-based presentation of generations of colourful UK phones.
• The History of the Telephone on Prince Edward Island Related Links and Files
  • 3-slot AE payphone information
• Telephone technology page good reference material but somewhat simplified.
• Brooke's Telephone Equipment data satellite, military, signalling, cell, telegraph, etc.
• Electrical Communication (1922-1966) a record of progress in the telephone, telegraph and radio art. Published quarterly by the International Western Electric Company.
• Bell Laboratories Record and other publications, broadcasting,
• Index to Bell System Technical Journal1922-1983 - by Sam Etler
• Western Union Technical Review published 1947-1969.

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  Unchecked possible sources of this sort of equipment

• Second Hand Radio
• Keane Machines, Inc.
• Used telecom equipment at Cherokee Wireless, Niles IL
• Used telecom equipment at Single Source Communications, Fremont NE
• Used equipment at Alliance Datacom, Dallas TX
• Search eBay for Tellabs or Wescom