Western Electric Anti-Sidetone Info.

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Before there was Anti-Sidetone, Sidetone was the name given to the quality of voice communications over early telephones.  Sidetone had one major disadvantage in that each party could hear themselves as well as the party they were talking to.  

With the introduction of Anti-sidetone in the early 1930's, which improved voice communications.    Earlier desk sets and desk stands (candlesticks) could be upgraded to anti-sidetone by adding more contacts to the switchhook assembly inside the base unit.   The desk sets changed from using the original model numbers to using the number on the base (A, B, C & D) as the model number to allow the sets to be wired for either sidetone or anti-sidetone.   Candlestick telephones that were upgraded to Anti-sidetone would have the digit "1" in front of the model number to show that it is an anti-sidetone set.     Example;  a 51AL sidetone dial desk stand would become a 151AL anti-sidetone desk stand.   

The subset is the unit that houses the electrical components to create either sidetone or anti-sidetone and make any telephone without an internal network or inductor to be a complete and operational telephone.  Some subsets also included components to allow the telephone set to ring.   

The Bell System made sure that all of their earlier equipment could & would be able to be upgrades as improvements were made in their system design.

With the introduction of the 302 telephone in 1937, which had all components inside a single enclosure, earlier telephones and their subsets became obsolete, but many remained in service through the 1950's & 1960's.  

The following is a list of model numbers of Sidetone & Anti-sidetone telephone sets from the 1920's & 1930's.

It was possible for an installer to install a new "D1" mount desk set using a 3 conductor mounting cord with a sidetone subset and wire the telephone as a "102" or install a "A1" mount desk set using a 4 conductor mounting cord and anti-sidetone subset and wire the telephone as a "202" using the Bell System Practices, known as "BSP's".   Later BSP's do not show the type of mounting used, "A1", "B1", "C1", "D1", "G-" , only the set wiring as 102,103,202,203, Etc.     

Refer to BSP # C31.101, issue 1, dated 2-15-33 for sidetone sets & BSP # C31.111, issue 1, dated 6-1-31 for anti-sidetone sets ( Why would the anti-sidetone BSP be issued before the sidetone BSP? )  

            Note: * = original introduced model

            Note:   * = original introduced model

SUBSETS

Subsets are connected to a telephone set with either a 3 or 4 conductor mounting cord and to a telephone line with either a 2 or 3 conductor mounting cord.

This section is not a complete list of subsets and is still under construction.

If you see any statement that is incorrect or can add anything to this page, please let us know.

Please E-mail us at:  Info@collectorville.com

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