No subject

Sat Sep 25 01:58:40 PDT 2010

Benno

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Hi,
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   Here is some additional material on the history of magnetic  recording,=
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excerpted from 'The Patent History of the Phonograph':
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   =20
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>>  (51).  661,619      Method of  Recording/Reproducing Sounds/Signals=20
Filed  July 8, 1899  (Valdemar  Poulsen)  Issued Nov 13,  1900=20

U.S.  Patent Office officials at first said of the steel-wire-wrapped, =20
stationary brass-cylinder magnetic recorder (40-seconds  duration) of =20
Valdemar  Poulsen (1869-1942)  that the Aalleged  invention is contrary to=
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the well established and universally recognized  principles of electricity=
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and magnetism,...@  After several letters from reliable officials (e.g. Dr=
.=20
C. W. Stiles, Scientific  Attache at the U.S. Embassy in Berlin), his=20
original application was divided,  with only three Claims allowed for his=
 first=20
patent - on the Method. The  remainder of the application (43 Claims for=
 the=20
Appara&shy;tus) did not issue  until May 29, 1906 (822,222);  both patents=
 had=20
to be Avalidated@  by a Feb. 19, 1903 act of Congress as the U.S.=20
application was filed a week past  the 7 months allowed after the Danish=
 grant and=20
the Patent Office had missed the  error. A mechanical method of=20
electro-magnetic recording and playback had been  anticipated by Edison=3D=
s  Caveat of Mar.=20
8, 1878 and a truly magnetic system was first conceived by  Oberlin Smith=
 of=20
Bridgeton, NJ, in a memorandum dated Sept. 24, 1878, which was  filed with=
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the Cumberland County Clerk in NJ. However, when Smith submitted his =20
official Caveat in Washington, DC on October 1-4,  1878, he Aaccidentally@=
 =20
omitted his reference to tempered steel wire magnetized in zones, and  sub=
stituted=20
a non=E2=80=91magnetic filament inter&shy;spersed with  magnetic  frag&shy=
;ments; =20
years  later,  in 1921/22,  Smith  also invented  a remote record changer=
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with 50 discs (the Autofono, 1,573,504). Some  work with magnetic recordin=
g=20
was done in 1887 in Germany, Holland and France by  Wilhelm Hedick (Ger.=
 pat.=20
42.471 & Brit. pat. 569/88), and Paul Janet.  Poulsen=3Ds  device, origina=
lly=20
designed for telephon&shy;ic record&shy;ing, was successfully  exhibited=
 at=20
the 1900 Paris Exposition with models manufac&shy;tured by Mix  & Genest=
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(wire diameter of 1/50O)  and captured the voice of Emperor Franz Joseph=
 on=20
Sept. 20 (the oldest surviving  magnetic recording), but the American=20
Telegra&shy;phone Co., formed by Stilson  Hutchins (an 1887 Graphophone su=
pporter) in=20
November 1903 to exploit  Poulsen=3Ds  patents, was a commer&shy;cial=20
failure; vacuum-tube amplifiers were not yet  invented and the high-speed=
 (.01O =20
dia.) wire-spools became entangled at 84O/sec.  and could not be more swif=
tly=20
rewound, while the 5.15O  discs (constant linear speed) were expensive and=
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of limited capacity. D-C  biasing was accomplished by Poulsen and Pedersen=
 in=20
their 873,083 (they ceased  their work after 1902), but AC high-frequency=
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bias recording was not invented  until 1918 by L. F. Fuller (1,459,202),=
  and=20
in 1921 by W. L. Carlson and G. W. Carpenter of the US Naval Research =20
Laboratory B  for signal transmission only (1,640,881).  The device had al=
so=20
been developed to include high-speed telegraphic recording  by Patrick B.=
=20
Delany. However, there were rumors of hostility from  dictation-phono&shy;=
graph=20
interests and the company did not flourish under  President Charles D. Roo=
d=20
(after July 1908), against whom charges of deliberate  non-development and=
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treason were made on Mar. 10, 1932; the occasion was a  failed legislative=
=20
attempt by 16,000 AmTelegCo. shareholders to extend G. S.  Tiffany=3Ds  as=
signed=20
(1909/1915) taut-wire improvement, 1,142,384, by eight years (S. 1301). =
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Poulsen=3Ds  Brit. pat. 8961 also failed of extension - in 1913. In additi=
on, NY=20
telephone  officials had somehow ascertained that one-third of their=20
serviced conversations  were illicit in some way and revenue would corresp=
ondingly=20
decline if these  customers feared the preservation of their words; not ti=
ll=20
1948 did limited  telephone-recording attachments become legal in the U.S.=
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Even the prominent  display of a steel-tape model, with the voice of Wm.=
 J.=20
Bryan, at the  (California) Panama-Pacific Exposition in 1915 did not igni=
te=20
sales. A  loud-speaking  disc Telegraphone was finally developed in 1920=
 by=20
Max Kohl A.G. of Chemnitz,  the founder of which had constructed Edison ti=
n=20
foil phonographs in 1878; an  outdoor model (with rail-embedded signals fo=
r=20
locomotives) was built around 1921  by A. Nasar&shy;isch&shy;wily. The=20
author of a later (1949)  study of magnetic recording, Semi J.  Begun, inv=
ented=20
a more commer&shy;cially successful model with removable  maga&shy;zines=
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called the Dailygraph in 1929. For connections to  sound-on-film,  see com=
ments=20
at Gaumont=3Ds  752,394. Poulsen=3Ds  attorney, Wm. A. Rosenbaum, who was=
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apparently responsible for the original late  filing, managed to obtain a=
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telegraphone patent himself (720,621) and later  became the Secretary of=
 the=20
American Telegraphone Co. (the company=3Ds  assets were sold off in 1936).=
 Cf. also=20
M. Camras=3D  later 2,351,003-011,  some of whose voice-recording work was=
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anticipated by Nagai, Sasaki and Endo in  1938 (Jap. pat. 136,997). <=20

hth.
=20
  Any luck on the German talking doll patent of 1894 (KuR)?
=20
Allen Koenigsberg
 _www.phonobooks.com_ (http://www.phonobooks.com)=20
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