One Tube Radio

Background

After Crystal Radios, that have no tubes and don't require any power other than the received signal, the next level of complexity is the one tube radio. It uses a regenerative circuit (Wiki) to get more gain from the single WD-11 (Wiki) tube.
Regenerative
Receiver schematic

Edwin Howard Armstrong (Wiki)

The popular inventor of the regenerative receiver as well as FM radio.

Lee De Forest (Wiki)

Patented the regenerative receiver prior to Armstrong and won the court battle over it. But De Forest was involved in a number of shady deals where he was sued and lost so although he really did invent the regenerative radio receiver seldom gets full credit.

Description

The major components are:
Variometer coil with 6 taps - top center dial rotates internal coil, lower center switch selects taps. The movable coil controls the regeneration.
6 Position Switch - controls the tuned frequency along with the variable cap.
Filament Rheostat - controls tube emission (early tube had wide varations in their gain.

Marked C-H Patent Applied For
It has two concentric shafts and two knobs, a coarse and fine knob.
Only two electrical terminals.
1672290 Potential-Control Apparatus, H.J. Wiegand (Cuttler-Hammer Mfg Co), Jun 5 1928, 338/134 ; 338/150 -

for regulating the plate and filament voltages on audion valves

Variable Capacitor - knob on left tuns capacitor, stations
Radiola WD tube socket - for WD-11 or equivalent tube.

1516837 Thermionic-tube Adapter, C.F Wright (Wireless Specialty Apparatus Co), Nov 25 1924 (filed Apr 4 1923), 439/655 -

specifically for using the UV 199 to replace the WD 11.

1696406 Radio Tube Socket, F.S. Masley & A.P. Wasil, Dec 25 1928, 439/573- specifically for the WD-11.
1913766 Method and Apparatus for Testing Audion Tube Circuits and Devices, J.H. Miller, Jun 13 1933, - Tube Tester

3 Meg Ohm resistor in a cylindrical glass holder very similar to a glass fuse except it has points on the ends to fit into the clip holder.
8 Terminals (2 more terminals used for internal wire connections)
1 & 2: Phones
3 & 4: Antenna and Ground
5 & 6 Filament "A" battery (at rear)
7 & 8: Plate "B" battery (at rear)

Schematic

The terminals are arranged to match the physical location. This is the Armstrong regenerative circuit. The plate is connected to the phones then the variable tickler coil.
It's not clear if the antenna and ground are reversed. The metal on the back of the front panel is connected to the upper terminal.

Patents

Class Numbers

Class 329 Demodulators
    347 AM
        367 Including regenerative feedback in non-oscillating demodulator
Class 375 Pulse or Digital Communications
    316 Receivers
        338 Interrupted Carrier Wave
            339 Carrier Controlling Local Generator
Class 455 Telecommunications,
    130 Receiver or Analog Modulated Signal Frequency Converter,
        334 With particular receiver circuit,
            336 Super-regenerative detector or discriminator

Patnets

879532 Space Telegraphy, Lee De Forest, Feb 18 1908, 329/368 ; 313/293; 315/355; 336/220 - Triode Vacuum Tube called an Audion at the time.

Has elements called the filament, grid and plate (in later patents called the wing).

1507016 Radio Signaling System, Lee De Forest, Sep 2 1924, 178/118 ; 331/171 - "kick-back" & progressive amplification mentioned (i.e. feedback)
1507017 Wireless Telegraph and Telephone System, Lee De Forest, Sep 2 1924, 370/339 -
There was a lawsuit between De Forest and Armstrong and De Forest won the suit (The Complete De Forest- Litigation)
Lee De Forest
patent 1507016 Regenerative Radio Receiver

Lee De Forest
patent 1507016 Regenerative Radio Receiver

1113149 Wireless Receiving System, Edwin H. Armstrong, Oct 6 1914, 375/339 ; 329/359; 455/321 -

Being in class 375 is interesting
The 1923 Crosley Harko ACE is marked "Manufactured under Armstrong U.S. patent 1113149".

Armstrong patent 1113149 Fig 6
Regenerative Receiver

1381692 Device for Receiving Radiotelegraphic and Radiotelephonic Signals, Cesare Bardeloni, June 14 1921 (filed April 12 1919), -

Regenerative
Oldest patent in class 455/336

1342885 Method of Receiving High-Frequency Oscillations, E. H. Armstrong, June 8 1920, 455/315 ; 330/165; 455/331
1415845 Selectively Opposing Impedance to Received Electrical Oscillations, M.I. Pupin & E. H. Armstrong, May 9 1922, 455/282 -
1416061 Radoreceiving System having High Selectivity, M.I. Pupin & E. H. Armstrong, May 16 1922, 375/338 ; 307/105 -
1424065 Signaling System, E. H. Armstrong, July 25 1922 (filed June 27 1921), 455/336 ; 329/359; 329/368; 329/370 -

Called Regenerative in this patent, but super regenerative in patent 1539821.
Second oldest patent in class 455/336

1472092 Receiver for Wireless Telegraphy, RCA, Oct 30 1923, 455/286 ; 455/290; 455/312; 455/315
1539821 Wave Signaling System, E. H. Armstrong (Westinghouse Elec), June 2 1925, 455/336 - two tube adjustable Super Regenerative
1611848 Wireless Receiving system for Continuous Waves, E. H. Armstrong (Westinghouse Elec), Dec 21 1926, 375/338 -
1502875 Tone Producing Radioreceiver, M.I. Pupin & E. H. Armstrong (Westinghouse Elec), July 29 1924, 375/339 -

1472583 Method of Maintaining Electyric Currents of Constant Frequency, W.G. Cady (RCA), Oct 30 1923, 331/163 ; 330/112; 331/158; 331/159; 331/164

RE17247 Method of Maintaining Electyric Currents of Constant Frequency, W.G. Cady (RCA), May 26 1929, 331/164 ; 310/318; 333/188 -
Fig 1 is the Armstrong circuit.
RCA patent
1472583 Fig 1 Armstrong regenerative radio

RCA patent
1472583 Fig 1 Armstrong regenerative radio

RCA 1922 Radiola Senior one tube radio patent dates:
1922 Radiola
Senior schematic diagram

Nov 7, 1905
Jan 15, 1907
Feb 18, 1908
Oct 6, 1914
May 10, 1921
Given the list of patent dates above the following may be the corresponding patents:
803569 Induction-Transformer for Wireless-Telegraphy Receiving-stations, Eugene Ducretet, Nov 7 1905, 455/292 - uses coherer and battery (not tube) -although not a regenerative radio, it's very close to the circuit,
804190 Instrument for Making Electrical Measurements, J.A. Fleming (Marconi), Nov 7 1905, - not the circuit, but interesting
841386 Wireless Telegraphy, Lee De Forest, Jan 15, 1907, 315/94 ; 313/147; 313/152; 313/157; 313/161; 313/581; 315/348; 315/349; 315/357; 329/322 - one tube
879532 Space Telegraphy, Lee De Forest, Feb 18 1908, -329/368 ; 313/293; 315/355; 336/220 one tube radio without feedback
1113149 Oct 6, 1914 (see Armstrong patent above)
1377405 Audion Circuit, Lee De Forest (De Forest Radio Telephone & Telegraph), May 10 1921, 330/103 ; 330/109; 330/185 - dual triode with feedback

Brooke's Crystal Radio Info
Brooke"s High Q Crystal Radio
Goof Proof Regenerative Receiver, 73's Nov 1990 - PCB from FAR Circuits
ARRL - High Performance Regenerative Receiver Design by Charles Kitchin, N1TEV, QEX Nov/Dec 1998, pg 24-36 - PCB from FAR Circuits
The New Radio Receiver Building Handbook by Lyle Russell Williams

Links

RCA Radiola III and III-A By Doug Criner - includes info on WD-11 tube substitutions
Dialcover by Bill Turner - parts and manuals
1922 Radiola Senior -

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