Author Topic: Automatic Electric Type 40 & 50 Monophone CB circuit and wiring  (Read 1996 times)


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Here are schematic diagrams for the Automatic Electric Type 40 desk telephone and the Type 50 wall set for standard common battery service.

The first is a circuit diagram drawn based on the instrument paper folds of wiring diagrams found inside an AE 40 set and the diagrams in the AE catalogs, as indicated on the drawing legend.  A circuit diagram is different from a wiring diagram.  A wiring diagram emphases connections, rather then electrical functioning, and often shows some components resembling physical objects. A circuit diagram emphasizes understanding of operation and components are shown purely symbolically expressing electrical functions, such as resistance, capacitance, and inductance.

The second and third are wiring schematics. AE Form D-53940 was one of several that can be found in sets. The second was printed in Canada (Issue 3) and the third is Issue 7 printed in the US.

The fourth image, shows Issue 9 of this instrument label, Form D-53940-A, printed in 1958 in Northlake, Ill.

Some preliminary discussion of these diagrams can be found in this topic: Regarding AE40 Receiver pop

A typical instrument type number or order number for these sets is an N-4020 or N-4023 with a low-impedance ringer, and a L-4123 having a high-impedance ringer.  For the Type 50 wall phones, common types are L-5000 and L-5100 for low- and high-impedance ringer sets.

PS: Finally, another circuit diagram that shows the identical same circuit, but in another layout that resembles the layout often used for WECo circuits. Indeed this version shows that the AE40 circuit is actually based on the WECo design.

PS: An older version of the circuit schematic was found on this "Unusual AE 40", Form D-53688 Issue 7.
« Last Edit: March 11, 2017, 05:35:55 PM by unbeldi »