Sounders & Relays

The telegraph sounder was developed after it became clear that operators were able to read the incoming telegraph signal by listening to the clicking sound produced by the telegraph register. The sounder was able to greatly amplify this clicking sound with various improvements in the acoustics of the instrument.

When the sounder lever is pulled down, it strikes against a metal post called an "anvil", which creates a sound. Many of the early anvils were just simple machined metal posts, which were not the best designs from an acoustics standpoint. So, some of the early sounder designs by instrument makers such as Charles Chester and Charles Williams employed an acoustic base, where the wooden base was hollow with a hole in the top or bottom to act like a resonator, much like a guitar. This helped amplify the sound.

With other later designs, the brass base on which the anvil and other parts were mounted was itself hollow, which also helped act as a sound amplifier. There were even designs where the anvil looked like a metal drum (see the Gilliland Drum Sounder below), providing even more sound amplification. Eventually though, the sounder settled on a common design with a hollowed brass base and a 2-legged anvil. This progression can be seen as you browse through the photo gallery below.

The exact date when telegraph sounders came into use is not known, but it is believed the first sounder was invented by James Clark & Co. from Philadelphia around 1856. There is a simple sounder that appears to have been created by modifying a relay in the collection of the Smithsonian Museum. A picture of this sounder can be seen in the photo gallery on this page.

Below are some pictures of Sounders and Relays dating from the 1850's up to the early 20th Century. Click on each thumbnail to view the full size image:

Relay by William Clark, Philadelphia. Ca. 1846 (Smithsonian Museum) William Clark Relay, Philadelphia. Ca. 1848 Another View of the Early William Clark Relay SW Chubbuck Relay, Utica NY. Ca. Early 1850's
Ornate Relay by Henry J. Rodgers, NY. Ca. 1850 Another View of the Rodgers Relay Early Caton Relay, Ottawa Ill. Ca. 1850's Palmer & Hall Relay, Boston. Ca. 1850's
Hinds & Williams, Boston. Ca. 1850's James Clark, Philadelphia. Ca. 1856. Possibly the First Telegraph Sounder (Smithsonian Museum) Acoustic Base Sounder. Charles Chester, NY. Ca. Late 1850's Another View of the Chester Sounder
Charles Chester Sounder. Ca. Late 1850's E. Holmes Burglar Alarm Relay. Ca. 1850's Thomas Hall, Boston. Ca. 1860

Unknown Maker. Ca. 1860's

William Lundberg, San Francisco. 1863 Early Phelps, American Telegraph Co. Ca. Early 1860's Phelps American Telegraph Co. Ca. Early 1860's GM Phelps, NY. Ca. 1860's
Robert Henning @ Caton Instrument Shops. Ca. 1860's Another Henning Sounder. Ca. 1860's A different version Henning Sounder. Ca. 1860's A.S. Chubbuck, Utica, NY. Ca. 1860's
Caton Relay. Ca. 1860's Acoustic Base Sounder. Charles Williams, Boston. Ca. 1860's Charles Williams, Boston. Ca. 1860's William Phelps, NY. Ca. 1860's
Charles T & JN Chester, NY. Ca. 1860's Shawk & Barton, Chicago. Ca. 1868 German Relay-Lewert. 1869 Phelps Round Base Sounder. Ca. 1870
Thomas Edison, NJ. Ca. 1870 Knox & Shain, Philadelphia. Ca. 1870 Knox & Shain Relay. Ca. 1870 LG Tillotson, NY. Ca. 1870
Sounder by LG Tillotson, NY with an Unusual Curved Frame. Ca. 1870 A Close-up of the Curved Frame Another View of the Tillotson Sounder Dominion Telegraph Box Relay, Canada. Ca. 1870
Davis & Watts Silver-Plated Pheasant Sounder, Baltimore. Ca. Early 1870's Another View of the Davis & Watts Pheasant Sounder RH Wilson, Ypsilanti, Michigan. Ca. Early 1870's Buell "Little Monitor" Sounder, Cleveland. Ca. Early 1870's
Electrical Construction Co. Cylindrical Box Relay, San Francisco. Ca. Early 1870's Electrical Construction Co. Sounder. Ca. Early 1870's Western Electric, Chicago. Ca. Early 1870's Miles Goodyear Sounder, Chicago. Ca. 1872
Davis & Watts, Baltimore. Ca. Early 1870's Another View of the Davis & Watts Sounder Early Tillotson Sounder, NY. Ca. Early 1870's LG Tillotson Relay. Ca. 1870's
"Uncle Sam" Sounder. William Davis, Jersey City. Ca. 1874 (Gil Schlehman K9WDY Collection) Splitdorf Castanet Sounder Patent Model, 1874 Dominion Telegraph Acoustic Base Sounder, Canadian. Ca. 1870's Another View of the Dominion Telegraph Sounder
Another Canadian Dominion Telegraph Sounder. Ca. 1870's Side View of the Dominion Sounder Western Electric, NY. Ca. 1870's Western Electric "Camelback" Sounder. Ca. 1870's
Knox & Shain, Philadelphia. Ca. 1870's Railroad Telegraph Supply Co, Chicago, Ca. 1870's. Likely Made by Western Electric Watts Sounder with B&O RR Markings, Baltimore. Ca. 1870's Another View of the Watts Sounder
Acoustic Base Sounder Marked "Wm. Hatteroth, SF". Likely Made by Electrical Construction & Maintenance Co. Underside of the Hatteroth Sounder Showing the Large Hole to Provide Better Acoustics M.A. Buell Private Line Sounder, Cleveland. Ca. 1870's Close-Up of Paint Job on Buell Sounder
Altoona Railroad Shops, Altoona PA. Ca. 1870's George Bliss, Chicago. Ca. 1870's George Bliss, Chicago. Ca. 1870's Partrick-Bunnell, NY. Ca. 1870's
Small Sounder Made by SH Hoggson, New Haven, Connecticut. Ca. 1870's Another View of the Hoggson Sounder Round-base Sounder by W. Hochhausen, NY. Ca. 1870's Another View of the Hochhausen Sounder
Jerome Redding, Boston. Ca. 1870's Partrick & Carter Private line Sounder, Philadelphia. Ca. 1870's Partrick & Carter. Ca. 1870's Partrick & Carter. Ca. 1875
M.A. Buell, Cleveland. Ca. Late 1870's M.A. Buell, Cleveland. Ca. Late 1870's Tillotson Sounder, NY. Ca. Late 1870's J.H. Bunnell, NY. 1877 Patent
Western Electric Split-Anvil Sounder. Ca. Early 1880's California Electrical Works, San Francisco. Ca. 1880 Altoona Shops Cain Sounder. Ca. 1881 JH Bunnell Sounder With 1882 Patent Base.
Partrick & Carter, Philadelphia. Ca. Early 1880's A.B. Lyman, Cleveland, "Bullnose" Sounder. Ca. Early 1880's Another View of the Lyman Bullnose Sounder William Davis Vertical Sounder, Jersey City. Ca. 1883
Viaduct Mfg, Baltimore. Ca 1880's Gilliland Drum Sounder. Made by James Gilliland, Indianapolis Indiana Ca. 1885 Another View of the Gilliland Drum Sounder P.B. Delaney Sounder, NY. Ca. 1880's
Western Electric Box Relay, Chicago. Ca. 1880's Jerome Redding, Boston. Ca. Late 1880's New Haven Clock Co. Sounder. Ca Late 1880's New Haven Clock Co. Relay. Ca. Late 1880's
Lewis & Fowler Mfg. Brooklyn NY. Ca. 1886-1887 Altoona Shops Sounder. Ca. Late 1880's C.H. DuBois, NY. Ca. Late 1880's British GPO Sounder. Ca. Late 1880's
British GPO Phelps-Style Sounder. Ca. 1880's E.S. Greeley Relay, NY. Ca. Late 1880's A.B. Lyman Leaf-Spring Pivot Sounder, Cleveland. Ca. 1890's Another View of the Lyman Leaf-Spring Pivot Sounder
A.B. Lyman "Rock Bottom" Sounder, Cleveland. Ca. 1890's JH Bunnell Repeating Sounder, NY. Ca. Late 1880's J.H. Bunnell Pole-Changer Relay. Ca. 1890's Western Electric, Chicago. Ca. 1890's
Western Electric Pole-Changer Relay. Ca. 1890's Western Electric Tube-Lever Sounder. Ca. 1890's E.S. Greeley Double Relay, NY. Ca. 1890's California Electrical Works Relay, San Francisco. Ca. 1890's
Francis Hatmaker. Ca. 1900 J.H. Bunnell Giant Sounder Pocket Watch Sounder. M&L.E.Co. NY. Ca. Early 1900's The Back of the Pocket Watch Sounder Showing the Name Inscription
Belgian Relay. Ca. Early 1900's Belgian Drum Sounder. Ca. Early 1900's Austrian Relay. Ca. Early 1900's German Relay. Ca. Early 1900's
British GPO Sounder in Resonator. Ca. Early 1900's Bunnell Polar Relay. Ca. 1900 Western Electric Polar Relay. Ca. 1900 Bunnell Ghegan Patent Sounder. Ca. 1905
Bunnell Ghegan Sounder (Different Version) Ca. 1910 Western Electric "Gooseneck" Relay. Ca. Early 1900's British A.T.M. Relay. 1918 Tillotson Sounder Converted to Spark Relay
Bunnell Mini Sounder. Ca. Early 1900's Foote-Pierson. Ca. Early 1900's Bunnell Secret Sounder. Ca. Early 1900's (Sounder Inside Headphone) Mascot Resonator Hood With Sounder
Standard Resonator Hood Swing-Arm Resonator Hood Bunnell Mainline Sounder, 1895 Patent. Ca. Early 1900's MESCO Sounder. Ca. Early 1900's
Western Union Type 3-B Sounder. Ca. Early 1900's Western Union Type 3-C Sounder. Ca. Early 1900's Western Union Type 15-B Mainline Sounder. Ca. Early 1900's Western Union Type 21-A Relay. Ca. Early 1900's
Western Union Type 7-A Sounder. Ca. Early 1900's Signal Electric Sounder, Menominee, Michigan. Ca. 1920's Signal Electric Relay. Ca. 1920's Art Deco Style Swedish Relay. Ca. 1920's




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