Wheatstone's telegraph receiver
Date: 1945-1960
Inventory Number: DW0887b
Classification: Telegraph Receiver
Subject:
Inventor: Sir Charles Wheatstone (1802 - 1875)
Maker: French
Dimensions:
19.4 × 18.4 × 8.6 cm (7 5/8 × 7 1/4 × 3 3/8 in.)
box: 14 × 26 × 19.7 cm (5 1/2 × 10 1/4 × 7 3/4 in.)
Accessories: part of a set that includes the transmitter (DW0887a)
DescriptionA telegraphic receiver that receives an incoming electrical signal and activates a pointer on a dial-like display of letters and numbers.
The receiver is housed in an upright wooden case mounted on a four-footed wooden base. The case has a pair of brass binding posts with knurled-edge adjustment screws, one mounted on each side. And additional two brass adjustment screws are mounted on the right side of the case.
A large, circular instrument dial, housed in a decorative brass frame and visible behind a glass window, displays a ring of letters, A-Z, and a smaller, partial inner ring of numbers, 1-9 and 0 arranged clockwise starting at the "12 O-clock" position on the dial. At the top of the dial are also the labels "ALPHABET," "+" and "CHIFFRES." A center-mounted pointer rotates to point to letters and numbers on the display.
Notice that it lacks a "W", probably as it was made for the French market.
The case, which is open on the top, has a hinged back which can be opened. Inside, a pair of electrical coils is mounted on a metal panel, and is connected to the binding posts and adjustment screws. The coils magnetize a "Y" shaped metal bracket which controls the needle on the dial.
The receiver is housed in an upright wooden case mounted on a four-footed wooden base. The case has a pair of brass binding posts with knurled-edge adjustment screws, one mounted on each side. And additional two brass adjustment screws are mounted on the right side of the case.
A large, circular instrument dial, housed in a decorative brass frame and visible behind a glass window, displays a ring of letters, A-Z, and a smaller, partial inner ring of numbers, 1-9 and 0 arranged clockwise starting at the "12 O-clock" position on the dial. At the top of the dial are also the labels "ALPHABET," "+" and "CHIFFRES." A center-mounted pointer rotates to point to letters and numbers on the display.
Notice that it lacks a "W", probably as it was made for the French market.
The case, which is open on the top, has a hinged back which can be opened. Inside, a pair of electrical coils is mounted on a metal panel, and is connected to the binding posts and adjustment screws. The coils magnetize a "Y" shaped metal bracket which controls the needle on the dial.
Signedunsigned
Inscribedprinted on instrument dial: + / ALFABET / CHIFFRES / A / B / C / D / E / F / G / H / I / J / K / L / M / N / O / P / Q/ R / S / T / U / V / W / X / Y / Z / 1 / 2/ 3 / 4 / 5 / 6 / 7 / 8 / 9 / 0
FunctionThis is a telegraph receiver based on the invention by Charles Wheatstone in the 1940s, for transmitting signals that would be displayed as letters of the alphabet at the receiving end, which was thought at the time to be beneficial as it would allow less skilled operators than other methods.
In these telegraphs, the received electric signal activates electromagnets that in turn press on an escapement mechanism, giving impulses to the pointer that make it move from one letter to the next. (See 'Function' in the transmitter, DW0887a, for details on the coding of the letters).
This telegraphy method was soon replaced by others based on the Morse code and direct listening by the operator.
The particular example shown here appears to be of a relatively late date, and it was probably made in France.
In these telegraphs, the received electric signal activates electromagnets that in turn press on an escapement mechanism, giving impulses to the pointer that make it move from one letter to the next. (See 'Function' in the transmitter, DW0887a, for details on the coding of the letters).
This telegraphy method was soon replaced by others based on the Morse code and direct listening by the operator.
The particular example shown here appears to be of a relatively late date, and it was probably made in France.
Primary SourcesA very good explanation of this telegraph can be found in:
Robert Sabine, The Electric Telegraph, London, 1867. pp. 82-84.Available in Google Books here.
Robert Sabine, The Electric Telegraph, London, 1867. pp. 82-84.Available in Google Books here.
ProvenanceAcquired in France, 1964.
