The Sparks Telegraph Key Review

Spark Components

The Spark Components page is very much in its infancy and is expected to take several years before it is near completion. This list will be updated as additional information becomes available. It is currently a work in progress. Please e-mail me with information on spark components not yet included on this list. The Spark Components list will concentrate on the components that were specific or original to spark transmitters, but not including the keys and complete transmitters themselves since they are treated on the Spark Key Project and the Spark Transmitter Project.


Company NameDateLocationComments
ACME Apparatus Co.QST ad Nov/1920Cambridge, MA Non-resonant transformers for high spark frequencies:
List No.12016 full power 250W
List No.12017 full power 500W
List No.12018 full power 1000W
ACME Wireless Construction Co.1909Cambridge, MA Probably same as ACME Apparatus Co. with older name.
Type A and Type B Helices & loading coils
Induction coils 1/2", 1", 1-1/2", 2"
Spark gaps
Type A, B & C transmitting condensers
Amalgamated Wireless Australasia1913Australia Formed from merger of Telefunken and Marconi interests in Australia.
Transmitting Helix
Plain Discharger (straight gap)
American Radio Sales & Service Co.QST ad July/1921Mansfield, OH DX-52 Oscillation Transformer
DX-51 Spark Gap
AMRAD American Radio and Research CorporationQST ad November/1919Medford Hillside, MA Lightning Switch 100A, 500V
Induction Coils:
Type C, 6 Volt
Type C1, 32 Volt

Quenched Gap
Type G-1 1 KW gap
Type G-2 1/2 KW gap
Type G-3 1/4 KW gap
Armorl (Armstrong-Orling)?England "Induction coils in all sizes" up to 20"
Benwood Specialty Co.QST ad Dec/1919St. Louis, MO "Benwood" Rotary Spark Gap
No.1 Benwood Gap complete
No.8 8 stud rotor
No.10 10 stud rotor
No.14 14 stud rotor
A.W. Bowman1911-1922+Lexington & Cambridge, MA Spark gap on 2-1/8" x 3-5/9" Bakelite base with name molded into it.
J.H. Bunnell & 1915New York Rotary and straight gaps sold under model names Beeko, Mascot, Dandy, and Jove
Spark Coil under brand name Mascot
F.B. Chambers & Co.QST ad Dec/1915Phila., PA Rotary spark gaps, mahogany or marble bases
spark coil
Chelsea Radio Co.QST ad Aug/1920Chelsea, MA Spark Load Coil (tapped loading inductance 0-3500 meters)
Chicago Radio LaboratoryQST ad Nov/1919Chicago, IL Hyrad synchronous rotary gap
Cino Radio Mfg. Co.QST ad Feb/1922Cincinnati, Ohio "Cino Sink" rotary gap and motor
Clapp-Easthambegan making radio equipment ca 1910Cambridge MA Type Y 658 Antenna Switch (Oct/1920 QST ad)
Semi-Quenched Cambridge Rotating Discharger (rotary gap) from 8/1916 ad
Rotary Spark Gap No. 741 (QST ad Oct/1920)
Type F656 spark gap
Oscillation transformers:
No. Y-200 1/2 KW and up
No. TXL-101-A International, up to 1 KW
No. Y-100 up to 1/2 KW
Type 651 oscillation transformer
Type 653 "radiocoupler" oscillation transformer
Type Z642 protective device (2 condensers across line)
Type ZRL high tension transformer for use with rotary gaps
Type L spark transformer (1/4, 1/2, & 1 KW spark coil)
1/4, 1/2, 1, 2, & 3 KW Type E transformers (spark coil)
High potential condensers F654, F655, F655A, F655B, F655C
Type 611 electrolytic interrupter
Continental Electric Co.QST ad January/1920New York, NY No. 1031 straight spark gap
Rotary spark gap
Doubleday-Hill Electric Co.QST ad April/1917Pittsburgh, PA Rotary gap
Dubilier Condenser Company1915New York Founded by William Dubilier, and merged in 1933 with Cornell Electric.
CD 53 and CD 53A Spark Type Protective Device; capacity 150 amps, 500 volts for 1,2,5, and 10 KW spark sets.
Mica transmitting condensers (CD 54, etc.)
Wm. B. Duck Co.QST ad May/1917Toledo, OHSome of these components probably only marketed by Duck and made by others.
Type "C" Sayville Gap (rotary gap, initially a Halcun product)
Type "D" Rotary spark gaps, in 1/2 KW and 1 KW rating
No.60X15A Zinc Spark Gap
No.60X15 Zinc Spark Gap
No.44X0 Spark Gap
No.A4018 Spark Gap with Porcelain Base
No.A4019 Standard Spark Gap with Porcelain Base (this made by J.H. Bunnell & Co.)
No.A395 Commercial Type Oscillation transformer
No.A7628 Oscillation transformer
No.A555 Junior Oscillation Transformer
No.39X0 1/4 inch spark coil
No.44X6 1 inch spark coil
No.40X0 1/2 inch spark coil
No.41X0 1.5" spark coil
No.42X0 2" spark coil
No.43X0 3" spark coil
No.44X0 4" spark coil
No.45X0 6" spark coil
Also offered "Bull Dog" type spark coils 1/4, 1/2, 1, 1-1/2, and 2" types
No.A560 Pancake Helix
High Voltage transformer in 1914 catalog, called a "Flexible step-up wireless transformer", adjustable by wingnut on top.
No.A1921 Solenoid Operated Antenna Switch
Flexible Step-Up Transformer No.63X0 (Type T-0), No.63X1 (Type T-1), No.63X2 (Type T-2), No.63X3 (Type T-3)
Rotary Spark Gap No.A442
Magnetic Key No.A1925
High Potential Condensers complete in rack (No.6051 to 6053, and No.A6100)
Model IX Glass Plate Condenser (No.A1923 and A1924)
1 KW Antenna Switch No.70X05
2 KW Antenna Switch No.70X06
Electrolytic Interruptor No.71X13 (parts individually can be ordered)
Ducretet1899-1919Paris, France Rotary Spark gap with rotating ball copper electrode
Economic Electric Co.1909 or earlier? to about 1920London, England Spark coils in at least 15 different spark lengths
Electric Machine Co.QST ad Nov/1920Indianapolis, IN "Bell" Rotary Spark Gap
Electro Importing Company
1904-1915+New York Components listed in the EICo Catalog 14, 1914:
Electro Zinc Spark Gap
Electro Commercial Spark Gap
Electro Sending Helix
Electro Commercial Oscillation Transformer
Electro Adjustable Sending Condenser
Electro Leyden Jars
Electro Adjustable High Tension Condensers
Electro 1/2 KW Transformer-Coil
Gernsback Electrolytic Interrupter
Electro Antenna Switch
Electro Wireless Lightning Switch
0.25 inch Bulldog spark coil dated 1912
0.5, 1.0 and 1.5 inch (Bulldog) spark coils (1914)
The "Electro" Rotary Spark Gap (1915)
The "Electro" Quenched Spark Gap (1915), 8 sections, capacity 1 KW
Electro-Set Co.1914Cleveland, OH 1/6 KW Closed Core High Tension Transformer
1/2, 3/4, and 1 KW Flexible Wireless Transformers
Electrolytic Interrupter
Electro-Set Box Type Spark Coils 1/8, 1/4, 1/2, 1, 2, 3 inch spark
No.801 Spark Gap
Senior Spark Gap
Electro-Set Special Air Cooled Spark Gap
Type "P" Rotary Spark Gap
Type "A" Rotary Spark Gap
Transmitting condensers
Leyden jars
No.606 Oscillation Helix for Small Stations
No.607 Loose coupled Oscillation Helix
No.610 Antenna Switch (for up to 1/2 kw)
No.611 Antenna Switch (for up to 1 kw)
No.612 Antenna Switch (for higher power)
No.615M Lightning Switch (60A rating)
No.616M Lightning Switch (100A rating)
No.617M Lightning Switch (100A, 600V rating)
Electro-Set Line Protector
Elliott Electric Co.QST ad May/1917Shreveport, LA Rotary gap
J. Herbert FerrisQST ad Jan/1917Royal Oak, MI Rotary Gap
Fisher1919? 1 KW air cooled (cooling flanges) straight spark gap
Fosco Corp.QST ad Jan/1917Chicago, IL "A-Motor" motor and aluminum rotary gap rotor
Franklin Sales Co.QST ad Oct/1920Chicago, IL Franklin Rotary Spark Gap (Hamilton Beach Motor) 1/2 to 1 KW
A.H. Grebe & Co.QST ad June/1920Richmond Hill, NY Type TGAC Synchronous Rotary Gap with 220V motor
Type TGAD Synchronous Rotary Gap with 110V motor
Both were also advertised by MESCO
Edward E. Hayward, Jr.QST ad May/1920Boston, MA Little Wonder Gap, Rotary Gap.
The High Tension Co.1916Westminster, England Standard 12" spark coil
200 watt spark coil
Hunt & McCree1917NY Spark coils 1/4" to 10"
J-Ray M'F'G Co.QST ad Mar/1921St. Louis, MO Rotary Spark Gap
Karlowa Radio Corp.QST ad Mar/1921Rock Island, IL K20A (with Motor) and K20B (Pulley drive only) rotary gap
Kilbourne & Clark1901-1920+Seattle, WA Antenna switches for commercial and amateur use-- contacts arranged in the shape of a triangle on electrose insulators.
Fr. Klingelfuss & Co.1903Basel, Switzerland Spark coils for 10-150 cm spark length
Klitzen Wireless Apparatus Co.QST ad 1916Racine, WI Klitzen Rotary Gap
Max Kohl A.G. 1909-1927+Chemnitz, Germany Large induction coil
Lowenstein Radio Co.1918, but drawings of Lowenstein keys as early as 1916 existBrooklyn NY Type No. SE-994 1/2 KW Antenna Switch
Type No. SE 1499 1/2 KW Lightning Switch
Manhattan Electric Supply Co.
ca. 1910New York Zinc straight spark gap List No.467 (by 1915)
"High Efficiency Spark Gap" List No.465 up to 1/4 KW capacity, hard rubber base and zinc terminals
Rotary spark gap (QST ad Dec/1915)
Spark coils in polished oak case with vibrator:
1/4", 1/2", 3/4", 1", 1-1/2", 2", 3", 4" operating on 5 dry cells, List Nos. 459-464, 495-6
Adjustable Primary condenser List No.439
Sending Helix No.484
Leyden Jars and Fixed Condensers
Antenna Switch List No.416
Antenna Switch List No.422
Improved Antenna Switch No.253 (looks like Clapp-Eastham Type Y 653)
Lightning Switch List No.384
Marconi 1899-1919
(Aldene, NJ plant mfg starts 1912)
England, Canada, New York and New Jersey Type S H Antenna Switch
Type I antenna switch
Marconi Model 230 10" Spark Coil
Type B3 Transformer (1914)

From Marconi Catalog of Used Apparatus:
Motor Starter No.201
Motor Generator and disc discharger No.200, and No.214
Starting Switch No.202
2 KW 240-cycle transformer No.206
High Potential transformer No.216
High potential condenser No.207 and 218
Oscillation transformer No.208
Aerial Tuning Inductance No.209
Non-synchronous spark discharger No.220
Oscillation transformer No.221
Aerial changeover switch No.213
W.D. MathewsQST ad May/1920Marlette, MI Improved Spark Gap
Mi-Kerm Radio Co.QST ad Sept/1921Burlington, IA Mi-Kerm Rotary Quenched Spark Gap
Murdock, Wm.J.founded 1896Chelsea, MA Beautiful oscillation transformer on wooden base. (No. 424)
Moulded Transmitting Condenser
No.440 Straight Spark Gap (1919) on hard rubber base

From April, 1910 catalog (transformers, condensers, spark gaps, and helices all in 1/4, 1/2, 1 & 2 KW sizes:

Transformers No.400, 110VAC 60 cycle with hard rubber pillars
Sending Condensers No.481, glass plate type, jar type on request
Straight Spark gaps No.441 on polished marble base
Helices No.421, copper ribbon
Antenna Switch No.462 on polished marble base
Sending Helix No. 420 wound with round copper wire

From 1913 catalog:
Transmitting Helix No.422
otherwise same as 1910

From 1920 catalog:
No.463 Antenna Switch
No.483 transmitting condenser
No.488 transmitting condenser
No.443 rotary spark gap
No.265, 266, 267 induction coils

Radiguet & Massiot1906Paris, France large & small size spark coils
Radio Apparatus Company of AmericaQST ad Sept/1916Phila., PA Hy-Tone Rotary spark gap
Radio Equipment Co.QST ad Feb/1921Boston, MA Rotary Spark Gap
Radiolectric Shopad QST Oct/1920Cleveland, OH "73" single blade antenna switch, Type A with Marble base and Type B with wooden base
Radio Supply & Mfg. Co.QST ad May/1921St. Paul, MI 4 or 8 tooth disc rotary gap
Ray-Di-CoQST ad Feb/1921Chicago, IL Synchronous Rotary Gap
H.A. Reverend Mfg. Co.QST ad Feb/1917Kansas City, MO Rotary Spark Gap
Saginaw Radio & Electric Co.QST ad July/1921Saginaw, MI Sag-Re-Co products, "improved" spark gap with interchangeable teeth
Shotton Radio Manufacturing Co.QST ad Dec/1920Scranton, PA "Shramco" Oscillation Transformer
Signal Electric Mfg. Co.QST ad Dec/1920Menominee, MI "Signal Switch" Aerial changeover switch (QST ad 11/21)
"Signal" Rotary Spark Gap Motor
E.J. Simon1915New York CE 613 antenna switch and board
L. Brainerd StrattonQST ad Feb/1917Oneida, NY The Monotone Quenched Gap
T & H Radio Co.QST ad June/1921Anthony, KS Type TH-1 Oscillation Transformer, smaller ribbon on primary
Type TH-2 Oscillation Transformer, larger ribbon on primary
TelefunkenQST ad April/1920Germany Pancake Type Oscillation Transformer, marketed by Radio Equipment Co. of Phila.,PA
Thordarson Electric Mfg. CoQST ad March/1921Chicago, IL Type R transformers 1 KVA, 0.75 KVA, 0.5 KVA
Type RS transformers 1 KVA, 0.5 KVA, 0.25 KVA
Oscillation transformer
Type T-OT Oscillation Transformer (QST ad Oct/1919)
8, 12, & 16 tooth rotary discs
Trumbull1915? 100 Amp Ground Switch
Twin City Radio Lab.QST ad July/1921St. Paul, MI The Arrow Disc "Spark-Thru" Type Rotary disc
United States Electrical Supply Co.1900New York Induction coil/gap for wireless telegraphy
WEACO Wireless Experimental Apparatus Co.QST ad Jan/1917Phila., PA Rotary Gap
Western Radio Electric Co. QST ad Aug/1920Los Angeles, CA WESRAD Oscillation Transformer designed for 200 meters, up to 1 KW
Wilcox LaboratoriesQST ad May/1920Lansing, MI "Wilcox" Rotary Gap
Winn Radio & Electric Mfg. Co.QST ad June/1920Chicago, IL "Winn" Transmitter Coil-- induction coil with interrupter, No. 210
Wireless Manufacturing Co.QST ad June/1920Canton, OH Rotary Spark Gap
Wireless Specialty Apparatus Company1907-1919Boston, MA Components from 1919 Catalog:
Antenna Switch, Type Q-S-5001
Lightning Switch, Type Q-S-5002
Antenna Switch Type Q-S-501
Faradon condensers
Lightning Switch, Type Q-S-5007
Rotary Spark Gap, Type Q-S-5006
Young & McCombsQST ad Oct/1920? Young & McCombs Rotary Spark Gap

With assistance from Tom French, Doug Palmer, John Firey, Pete Malvasi, August Link, Chuck Brydges, Mike Feher, and many others!
Picture Credits:
Tom French-- Bowman gap
Pete Malvasi-- Murdoch oscillation transformer
Chuck Brydges-- 0.25 inch Bulldog spark coil
Mike Feher-- Marconi Type B3 Transformer

Russ Kleinman WA5Y
Last modified: January 10, 2005

FIRSTS! in the History of Wireless

Try guessing when you think the event on the left took place, then click on the event and the date will show to the right!

Back to the Spark Key Project
Back to the Spark Transmitters Project
Back to the Index
Back to the Spark Keys page
Original Research Material at Sparks Telegraph Key Review
Sparks Telegraph Key Review Library