I recently found this on ebay. Looks interesting
I wonder what the correct handset type was foer this and whether it had an internal network or external subset
https://www.ebay.com/itm/Stromberg-Carlson-Industrial-Rotary-Dial-Telephone-Parts-Restoration/322716571091
?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D47301%26meid%3Dedc40ba56e784b888fd8d5
46371cf2ad%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D142636991234&_trksid=p2047675.c100005.m1851
Mark
I have seen these some of thses with an ind coil . Use the handset off a 1243 set not sure of model number
The set is a 1232-type.
There's a wiring diagram in the TCI Library.
http://www.telephonecollectors.info/index.php/browse/wiring-diagrams-technical-library/stromberg-carlson-1/2085-1232-1233-1234-sc1232-3-4-tl?highlight=WzEyMzJd (http://www.telephonecollectors.info/index.php/browse/wiring-diagrams-technical-library/stromberg-carlson-1/2085-1232-1233-1234-sc1232-3-4-tl?highlight=WzEyMzJd)
Many of the components are shown in this catalog excerpt:
http://doc.telephonecollectors.info/dm/Stromberg%20Carlson%20Instruments.pdf (http://doc.telephonecollectors.info/dm/Stromberg%20Carlson%20Instruments.pdf)
Unfortunately, it doesn't include the 1232, so I've attached a quick snapshot of some info below. The photos shown have a later plastic handset (late production). As Robby said, most are found with the earlier bakelite 20-type handset shown in the line drawing on the right page (61A).