Capehart-Farnsworth timeline: 400 series Pick-ups

This article should show at last the overview about the different main parts that form a series 400 model. In fact this comprises also series 300, 200 and 100, the so called DeLuxe models with turn-over mechanism. I try to show each of the important items in a separate thread. It covers 1931 to 1950, the whole lifetime of this concept.

The intention is to show at last different threads for cabinets, Escutcheons/scales/knobs, record changers, tuner chassis and amplifier chassis, loudspeakers and pick-ups. For more or other information there is the general thread Capehart Radio-Phonographs for the 1930s and 1940s.

Capehart-Farnsworth timeline:
400 series Pick-ups (pickups)

The series started for the season 1931/32 without "season suffix" and followed with A, B, etc.
I use small pictures - with links to the big sized pictures - to keep this as an overview rather than a long thread ...

Would you have some pictures to document this better?
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First saison: 1931/32 - no suffix

 

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A = 1932/33

 

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B = 1933/34

 

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C = 1934/35

 

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D = 1935/36

 

 

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E = 1936/37

 

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F = 1937/38

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G = 1938/39

The first series 100 (only with 110G) was called Panamuse. From about season K, the drop type changer was introduced for (2 digit name) Panamuse and the models with the turn-over changer became the suffix "DeLuxe".

 

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H = 1939/40

 

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K = 1940/41

 

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M = 1941/42

 

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N = 1945-48

 

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P = 1948-50 - last series

End

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It is interesting to see the different view - but also the common view one had at the beginning of introduction of the "electric pick-up" - compared with later opinions and methods.

It all started with mechanical only sound pick-up's, followed by electrodynamic sound transducers, which later are also used for guitars and other mainly stringed musical instruments. For instruments today one uses mainly piezoelectric pickups as sensors or even optical devices.

Patent Woodroffe, pictures rearranged for a shorter post

The usage started with electric pick-ups with pillar terminals or flying leads as add-on devices, but soon whole pick-ups with the arm were avalable. At least John Baden Woodroffe (of London, GB) patented an electric pick-up which could be mounted directly by exchanging for the sound box of an acoustic spring-driven gramophone. It was filed January 22, 1927 in the UK and May 28, 1927 in the USA, granted in the US April 30, 1929 as patent 1,711,192. Bewlow you find why this was not the first patent on this.

Astonishing early is a patent filed September 3, 1928 in New Zealand, August 27, 1929 in the USA by Robert Douglas Cargill of Christchurch, US patent number 1,868,304 for a tangential play (longitudinally) instead of a tone arm. Tone arms describe an arch when moving to the center and thus becoming jambed against the sides of the volute groove of the record. This results in a seriously detrimental effect upon the reproduction and excessve wear of the grooves.

Also early one wanted to reduce weight on the stylus (needle) by not having the full weight of the tone arm. It was achieved with counterweights or better with a tone arm which does not hang but has a fork with a hinge so that only the tone chamber isthe weight and this sometimes with a counterweight by having the axis near the middle of it. Jean Dieux of Paris, France filed a patent for that in May 10, 1928, in the USA in March 1, 1929, becoming US patent 1,780,378.

For phonographs, the history is from "crude magnetic pick-ups" to robust "piezo-electric crystal pickups" with a substantial signal level - but unwanted distortions. Today they have the problem of the deteriorated jelly to protect the hygroscopic crystal from moisture, which would make it dissolve. The next development was the "ceramic cartridge" - as a piezoelectric with better materials. These are sensitive and have lower tracking force, so reduce wear to disc and stylus - and allow ceramic stereo cartridges. During the 1950s to 1970s they were common for low quality phonographs.

Better instruments for Hi-Fi were using then more "modern magnetic cartridges". Better amplifiers provided often two phonograph inputs, typically "CER" for ceramic and "MAG" for magnetic systems. For the latter soon two systems were in use: MM for moving magnet (common) - or MC for moving coil (dynamic). Normally a diamond is used for the stylus. Later in the 1970s the low cost magnetic cartridges made the ceramic obsolete. Only some used for 10 kOhm instead of 47 kOhm (Roxette TX88) extended the life time and could be put to the MM input. There are also exotic systems like "strain-gauge cartridges" which have to use a special preamp with steady current or "optical laser turntables".

Capehart

Many patents followed after J.B. Woodroffe. The patent of William H. Hutter is special in regard of Capehart changers. It was filed November 19, 1928 as serial no. 320,259 and patented January 6, 1931 as 1,787,579 for a "Translating Device": William H. Hutter, of Racine, Wisconsin, Assignor to Webster Electric Company, of Racine, the manufacturer of the early (amplifier) chassis for Capehart.

He gives no reference to other patents in this field, but at that time it was also not usual. It is known that Western Electric started with electrical recording several years before and it was introduced by Victor & Columbia in 1925. WE was then well known for microphones and amplifiers. But electrical reproduction followed already in December 1925 with the "Panatrope 10" from Brunswick. The principle itself of sound conversion was from Alexander Graham Bell, 1876, but others, including Michael Faraday, have shown this possibility even decades before. Also the early headphones used this electromagnetic conversion - decades before electric pick-ups. They might be used with a stylus attached quite soon after WW1 and after amplifiers could be used for that.

An other patent filed by Hutter is for "Phonograph Pick-up, filed October 13, 1930, patented November 14, 1933 as US number 1,934,857, still assignor to Webster Electric. Just one photo here of many and 8 claims:

His patent 1,846,871 for "Electric Phonograph Pick-up", filed September 4, 1930, patented February 23, 1932 was also assigned to Webster. It is more familiar for Capehart:

The soon connection Hutter / Capehart can be detected here.

W. H. Hutter filed a patent for "phonograph Pick-up mechanism" in August 17, 1931, serial number 557,489 with 6 claims. This was patented July 31, 1934 as number 1,968,149 for William H. Hutter, Fort Wayne, Ind., assignor to The Capehart Corporation.

I just bring in here the drawings and the first text page (of two). Thy can just be read. This is more for curiosity - and some information about the problems that had to be solved.

This form of the arm and tone chamber is at least reflected here for 406D of 1935/36.

Hutter filed in March 3, 1932 a patent for "Accustic Apparatus", which was patented in June 6, 1933 as number 1,912,454 without assignement. I could not find an other one assigned to Capehart.

Interesting is to see that Hutter patented in 1935 for Rock-Ola a "Phonograph Apparatus", US  patent number 2,058,693 of Oct. 27, 1936. One big problem was the electro-accustical fee-back through the supporting frame etc. Also his US patent 2,080,275 is for Rock-Ola and later patents until the WW2. After WW2 only his name shows up in his patents.

But Capehart got also some patents by Mesne Assignments like for instance a device for needle-changing, filed by John R. Mitchell of Dallas, Texas in August 17, 1828, becoming patent number 1,746,550. Not to forget the patent 1,872,707 for the turn-over mechanism by Ralph. R. Erbe of Tacoma, Wasthington, filed April 16, 1928, becoming patent number 1,872,706 or the one by him, filed April 5, 1929 or from Joseph Arnold Darwin, East Orange, NJ, filed July 28, 1931, becoming patent number 1,920,360. Or from Thomas W. Small of Huntington, Indiana, filed July 9, 1928 as "Automatic Graphophone", becoming patent number 1,792,553, the one filed by him January 4, 1929, becoming patent number 1,971,584 or the one filed by him July 21, 1930, becoming patent number 1,854,960. This is only a few of more than 30 such patents for Capehart.

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The first patent for an electro-magnetic transducer

April 7, 1890, Frank Lushbaugh Capps (July 28, 1869 - June 2, 1943) filed a patent, simply called "Telephone" (serial 346,814) and November 25, 1890 it was granted as patent number 441,396.

But Frank L. Capps was mainly busy with phonographs which demonstrate several patents, the first for gramophones perhaps the improved spring-motor phonograph in 1895, called "the Triumph" - for running 45 minutes on a single winding. Then there are patents like 1,290,712 for an Electric-Motor Phonograph as "Frank L. Capps, of Brooklyn, New York, Assignor to Pathe Freres Phonograph Company of New York, NY, a Corporation of Dalaware, Executed Dec. 29, 1916. Filed Jan 5, 1917, serial No. 140,668." But there are more, like patent 1,291,398 (and 1,293,489) for a "Talking-Machine" as Assignor to American Graphophone Company, of Bridgeport, Cennnecticut or for Pathe patent 1,324,643 for "Adjustable Sound-Box" etc.

Interesting is also the note of Elizabeth McLeod: "So far as is known the earliest actual broadcast recording known to survive is from a series of New York Philharmonic musical broadcasts recorded by Bell Laboratories in late 1923. At least one of these recordings predates by a short time the recording of former President Woodrow Wilson's talk on the meaning of Armistice Day recorded off WEAF by Frank L. Capps of New York on 11/10/23. The Wilson talk appears to be the earliest surviving recording of a voice broadcast.
As has often been pointed out, the recordings circulating which purport to be the KDKA election night coverage from 1920 are recreations. The 1920 campaign speech by vice presidential candidate Franklin Roosevelt in the Museum of Television and Radio's collection comes from a "Nation's Forum" phonograph record, and I've seen no documentation to support the claim that it is a broadcast recording. The "Nation's Forum" records were made in a studio by conventional acoustic-recording methods, and were not made from broadcasts or for broadcasting."

As "The Frank L. Capps Phonograph Co." and "Frank L. Capps & Co." he later had its own business for needles, mostly sapphire needles for recording (1940 with 15 employees). Address in 1940: 244 West 49th Street, New York City. He seemed also to have produced microphones, best known for condenser microphones, but offering also dynamic and crystal microphones. Microphone model CR BB was $ 36.

We can say that his patent 441,396 not only revolutioned the telephone and allowed headphones but also the pick-ups.

 

In the Master thesis by Nokolas T. Vitt we can read on page 31f:
"The balanced armature transducer was originally developed for use in telephones and other electroacoustic applications, including large headphones and tabletop radio loudspeakers. In his book, "Electroacoustics", Hunt offers an excellent historical background of electroacoustic transducers, including the balanced armature transducer. The history of the balanced armature transducer discussed below is drawn primarily from Hunt and is similar to a summary performed previously within this group by Smith in 2010.
It could be argued that the birth of the balanced armature transducer ultimately stems from the monumental discovery of electromagnetism, which was first observed in 1802 by Gian Domenico Romagnosi who noticed that a magnetic needle would move in the presence of a galvanic current.
In 1831, Joseph Henry demonstrated a telegraph that, according to Hunt, was the first device to “make
use of the linear attraction of an armature by an intermittent electromagnet (in contrast with the deflection of a magnetic needle)”. In 1877, Ernst Werner Siemens filed a patent that, as Hunt describes, “disclosed not only the moving coil mechanism, but also the basic elements of the balanced armature transducer.”
In 1880, Alexander Graham Bell’s assistant, Thomas A. Watson, described an “early form” of the balanced armature. In Watson’s design, the coil was attached to the armature and thus moved with it. However, it was not until 1890 that Frank L. Capps filed a patent in which the balanced armature transducer design was more definitively established. Capps improved Watson’s design
by fixing the position of the coil and allowing the now lightweight armature to armature to oscillate within the coil. In 1913, Nathaniel Baldwin developed and patented a set of headphones, which used a balanced armature transducer similar to the one described by Capps and a thin mica diaphragm. In 1921, Henry C. Egerton developed and patented a loudspeaker that used a balanced armature motor   In 1922-1923, Raymond L. Wegel also incorporated a balanced armature transducer into a Western Electric loudspeaker.
Starting in the mid-1920’s, the electrodynamic transducer became the dominant design for physically large applications such as the loudspeakers and headphones mentioned above."

In "Radio News", March 1931, page 810 and 811 we find an article "ElectromagneticPickups" by S. McClatchie. The first two pages may be of interest here.

You can click the two pictures to readable big size.

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