Single slot. Description, Installation, and Programming Manual. Contributed by John Novack.

Contributed and scanned by John Novack. Processed by Paul Fassbender.

Owner's Manual with schematic diagram. The Realistic DUoFONE Electronic Telephone Amplifier System provides "hands-free" telephone conversations at home or office. Radio Shack Catalog 43-278.

Contributed by Kurt Rudolph. OCR and bookmarks by Paul Fassbender.

Contributed by Dave Hunter.

Schematic extracted from the Owners Manual for printing.  Page 1 is full page.  Pages 2 and 3 each have half the diagram for larger print on 8 1/2 x 11 paper.  When printing, remember to set the printer driver to reduce the page to the print area of your printer.  Note that the source document was 5 1/2" x 8 1/2" and the print was tiny.

Dietrich Arbenz identified the housing used for the desk set as coming from the Siemens & Halske Fgtist 282. Its colors indicate that is an early model from the second half of the 1950s. Both were apparently unmodified by RCA. The wall set's housing is from a Fgstat 23, from the same period. Contributed and scanned by John Novack. Processed by Paul Fassbender.

From auction snapshots taken by Thomas Egan. Processed by Paul Fassbender.

A better scan and additional info would be appreciated.

Cover letter from Fonetron, Inc.  Submitted by Rick Walsh.

Contributed by Doug Alderdice and John Novack.

60 pages. Installation and Operation. Contributed by Hubert Miller. Scanning and OCR by John Novack.

Contributed by Steve Cichorsky. OCR by Clint Galliland.  [Original was archived]

Contributed by Steve Cichorsky.

Contributed by Steve Cichorsky. OCR by Remco Enthoven. Processed by Paul Fassbender.

Please note this file is in German.

Catalogue of German origin with text in German, English French and Spanish from around 1905, 116 pages.