musical telephone transmitter of the type designed by Philipp Reis
Date: circa 1863
Inventory Number: 8000a
Classification: Telephone
Subject:
Maker: Rudolph Koenig (1832 - 1901)
Owner: Jefferson Physical Laboratory, Harvard University (founded 1884)
Cultural Region:
Place of Origin:
Dimensions:
13.3 × 20.1 × 12.3 cm (5 1/4 × 7 15/16 × 4 13/16 in.)
box: 14 × 29.8 × 26 cm (5 1/2 × 11 3/4 × 10 1/4 in.)
Accessories: repeater (item 8000b)
DescriptionFirst device for electrical reproduction of sound at a distance. It was invented by Philip Reis, a professor of Natural Philosophy at the Boy's Academy of Friedrichsdorf, Germany, and produced by Rudolph Koenig from 1862 through the 1870s.
A musical tune played into the conical mouthpiece creates vibrations in the air which are received into the box. The box collects and concentrates the sound, and in the upper part of the box, a membrane vibrates in response. The vibrations cause breaks in an electric current, which are transmitted to the receiver.
The transmitter circuit is constructed of two platinum contact points in a mercury cup, driven by the vibration of a skin diaphragm. The transmitter and receiver each also have a telegraph key, for signaling the other party.
The transmitter's wooden case has a hinged lid and a latch, and a brass mouthpiece mounted on the front. On one side, a pair of wire coils is mounted, with the telegraph key positioned above them. On each side of the box is a brass terminal. The inside of the box lid has a circular opening, and contains the diaphragm. A contact point on the inside of the lid is connected by a coiled wire to elements inside the box.
The left side is stamped with Harvard number, "7-49"; stamped on top front right corner, "RUDOLPH KOENIG A PARIS"
This instrument was used in legal attacks on Alexander Graham Bell's telephone patents.
The transmitter has an accompanying repeater, item 8000b.
A musical tune played into the conical mouthpiece creates vibrations in the air which are received into the box. The box collects and concentrates the sound, and in the upper part of the box, a membrane vibrates in response. The vibrations cause breaks in an electric current, which are transmitted to the receiver.
The transmitter circuit is constructed of two platinum contact points in a mercury cup, driven by the vibration of a skin diaphragm. The transmitter and receiver each also have a telegraph key, for signaling the other party.
The transmitter's wooden case has a hinged lid and a latch, and a brass mouthpiece mounted on the front. On one side, a pair of wire coils is mounted, with the telegraph key positioned above them. On each side of the box is a brass terminal. The inside of the box lid has a circular opening, and contains the diaphragm. A contact point on the inside of the lid is connected by a coiled wire to elements inside the box.
The left side is stamped with Harvard number, "7-49"; stamped on top front right corner, "RUDOLPH KOENIG A PARIS"
This instrument was used in legal attacks on Alexander Graham Bell's telephone patents.
The transmitter has an accompanying repeater, item 8000b.
Signedstamped top front right corner: RUDOLPH KOENIG A PARIS
Inscribedleft side stamped with Harvard number: 7-49; stamped top front right corner: RUDOLPH KOENIG A PARIS
Functiontelephone transmitter [and receiver]
Curatorial RemarksHoused in a blue board tray with 8000b. SMS 9/27/2000
ProvenanceJefferson Laboratory, Physics Department, Harvard University
Published ReferencesThis instrument is described in:
Thomas G. Hedberg, "Catalogue: Telephones, Phonographs and Related Instruments in The Collection of Historical Scientific Instruments at Harvard University." William Andrewes, Project Director (unpublished manuscript, President and Fellows of Harvard College and Thomas G. Hedberg, 1989. Fifth Draft), pp. 13-15.
See also:
William Henry Preece and Julius Maier, The Telephone (London: Whittaker & Co., 1889), pp.94-97.
