Most collectors of WB400 or WB1400 equipment will not need to refer to the circuit diagrams on this page. As I have created these for my own research from microfilm, they are shared in case you find them useful.
Printing the Diagrams
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WB1400 Circuit Diagrams
Printing and Viewing Tips
The table below contains links to the most useful diagrams. As these are large in size, if you simply click the link the Browser will shrink the picture to fit your window and all the details will be invisible.
Please RIGHT-CLICK the photograph link and Save As... to your hard disk for viewing or printing later.
Loudspeaker WB1400
The plastic office version - WB29663
Circuit Diagram
Loudspeaker WB1401
The ruggedised version for damp areas - WB29664
Circuit Diagram
Receiver Speech WB1400
Warning Broadcast Receiver Box WB29759
Circuit Diagram
Block Schematic
Receiver Signalling WB1400
The Siren Control Receiver WB29452
Circuit Diagram
Block Schematic
Wiring at Customers Premises
Printing and Viewing Tips
The table below contains links to the most useful diagrams. As these are large in size, if you simply click the link the Browser will shrink the picture to fit your window and all the details will be invisible.
Please RIGHT-CLICK the photograph link and Save As... to your hard disk for viewing or printing later.
Line Powered Receiver Speech WB1400
Wiring Diagram WB29670 Sh1 (800W x 1200H pixels)
Wiring Diagram
Line Monitored Receiver Signalling WB1400
Wiring Diagram WB29670 Sh2 (800W x 1200H pixels)
Wiring Diagram
Locally Powered Receiver Speech WB1400
Wiring Diagram WB29670 Sh3 (800W x 1200H pixels)
Wiring Diagram
Locally Monitored Receiver Signalling WB1400
Wiring Diagram WB29670 Sh4 (800W x 1200H pixels)
Wiring Diagram
Receiver Speech at ROC Post
Wiring Diagram WB29670 Sh5 (800W x 1200H pixels)
Wiring Diagram
Combined site with both Receiver Speech & Signalling
Wiring Diagram WB29670 Sh6 (800W x 1200H pixels)
Wiring Diagram
Receiver Signalling at HV Substation
Wiring Diagram WB29670 Sh7 (1500W x 1100H pixels)
Wiring Diagram
Receiver Speech at HV Substation
Wiring Diagram WB29670 Sh8 (1500W x 1100H pixels)
Wiring Diagram
Provision on Loaded Local Lines
Wiring Diagram WB29670 Sh9 (800W x 1200H pixels)
Wiring Diagram
Exchange End of ROC Post Circuit
Wiring Diagram WB29670 Sh10 (800W x 1200H pixels)
Wiring Diagram
Monitor Unit WB1400
Mains operated power supply and monitor alarm WB29751, which is used for Locally Monitored Receiver Signalling ( WB29670 sht 4)
Circuit Diagram
Block Schematic
Filter Unit WB1410
Wiring Diagram WB29747 Sh1 (800W x 1200H pixels)
Wiring Diagram
Exchange Equipment
Printing and Viewing Tips
The table below contains links to the most useful diagrams. As these are large in size, if you simply click the link the Browser will shrink the picture to fit your window and all the details will be invisible.
Please RIGHT-CLICK the photograph link and Save As... to your hard disk for viewing or printing later.
Unit WB1400/1B
Audio Feed and Call Detector : WB29600
Circuit Diagram
Block Schematic
Unit WB1400/2B
Receive Amplifier : WB29596
Circuit Diagram
Block Schematic
Unit WB1400/4B
Distribution Amplifier : WB29601
Circuit Diagram
Block Schematic
Unit WB1400/5B
Local Line Power and Monitor Unit : WB29738
Circuit Diagram
Block Schematic
Unit WB1400/7B
X & Y Path Changeover Unit : WB29599
Circuit Diagram
Block Schematic
Unit WB1400/8B
Alarm and Power Unit : WB29581
Circuit Diagram
Unit WB1400/10A
Signalling Unit [UKWMO Group] : WB29692
Circuit Diagram
Signalling Voltages
Equipment Carrier WB1401
Control Point Exchange : WB29603
Block Schematic
Equipment Carrier WB1402
Distribution Exchange : WB29604
Block Schematic
Filter Unit WB1400
Filter on the distribution shelf : WB29602s1
Circuit Diagram
Filter Unit WB1402
Filter on the distribution shelf : WB29624
Circuit Diagram
Miscellaneous
Printing and Viewing Tips
The table below contains links to the most useful diagrams. As these are large in size, if you simply click the link the Browser will shrink the picture to fit your window and all the details will be invisible.
Please RIGHT-CLICK the photograph link and Save As... to your hard disk for viewing or printing later.
CCP Tone Sequences
WB29641 Sht4, All the speech and Signalling tone sequences and durations
Chart
CCP Flexible Cable Spec
WBW29607 Sht10, Wiring of the plug and cable connecting the CCP to the Terminating Unit
Diagram
Terminating Unit WB1400
WB29628 Sht1, Unit at secondary location, supplies power and terminates external lines
Power Supply Diagram
Unit Wiring
Power Unit WB1400
WB29742 Mains Power Unit within the Terminating Unit WB1400
Circuit Diagram
Tester WB1402
The CCP Tester : WB29755
Circuit Diagram
Block Schematic
Older ERA 1 Communications
Printing and Viewing Tips
The table below contains links to the most useful diagrams. As these are large in size, if you simply click the link the Browser will shrink the picture to fit your window and all the details will be invisible.
Please RIGHT-CLICK the photograph link and Save As... to your hard disk for viewing or printing later.
Receiver Carrier WB400A
WB28013, circuit diagram of carrier receiver
Circuit Diagram
Balancing Unit WB400A
WB28083, Used to reduce radio interference pickup on WB400 and latterly WB1400 signals
Circuit Diagram
ROC Post wiring with a Unit Intercom AD3460, Teletalk and WB400
ROC Monitoring Post in ERA1 with Grey Box Teletalk and WB400 receiver.
The Documents from BT Archives are Copyright BT Heritage, licensed under a