J.W. Miller Company
Catalog #58 (36 pages)
https://worldradiohistory.com/Archive-Early-Radio-Assorted/CATALOGS/Miller-Coils-Catalog-58.pdfCatalog #61 (177 pages)
http://www.tubebooks.org/file_downloads/Miller_No-61_.pdfPage 26 : Iron Core Transformers
612-Q models are 525 kHz, 500-550 kHz Range
Schematic diagrams of cores (#83) found on Page 36612-Q1 : Input
612-Q2 : Interstate
612-Q3 : Full-Wave* diagram #84
612-Q4 : Half-Wave
===
Radio Museum : E.M. Sargent WAC-44
Single conversion superhet with 2 stages of RF with individual front panel trimmers for the two RF stages and "first detector" (aka mixer) stage.
https://www.radiomuseum.org/r/sargent_wac_44.htmlAntique Radio Forum
Restoration of WAC-44 Receiver by Rodger, WQ9E (Central Illinois)
https://www.antiqueradios.com/forums/viewtopic.php?f=5&t=401293==
E.M. Sargent, an old shipboard radio operator, started the E. M. Sargent Co. in his home in 1924.
In 1926, he designed the Infradyne Circuit as a means to circumvent the Superheterodyne Patent (see forum).
His 1928 Amateur Radio license was W6SC.
A couple of early receivers, the "Long-Distance De Luxe" and the SW201 were produced in 1930/1931 by an affiliate company, the Radio Constructors Co.
Later Sargent built normal superhets, for instance model 11.MA and some others - most often commercial double conversion sets.
In 1934 the company moved to its definitive address, at 212 Ninth St., where they operated until the production of their last receiver in 1940.
In 1948 Sargent sold his stock to L.C. Rayment, who formed with his son the Sargent-Rayment Co., to produce hi-fi equipment.
E.M. Sargent died in 1948 at the age of 56.