e ?
Apparently the model requirement was abolished in 1880. Preparing them cost the inventor time and money, and worked against secrecy. The Commissioner for Patents may still request one:
On a sunny day (Thu, 15 Mar 2012 10:22:42 -0700) it happened Joerg wrote in :
In that link they mention the Ampex VRX1000 as needing no * transistors. I worked with that type machine :-)
Adventurous days! I had many footsteps in that studio.. Man do I remember that fire.
A Dutch Reformed Church turned into a TV studio ... oh man ...
So who shot Bambi and hung her up in the stair case?
-- Regards, Joerg http://www.analogconsultants.com/
Reduction to practice really only applies in interference cases. IANAL but I'm pretty sure that you can't invalidate an issued patent by arguing that it was never reduced to practice.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
units
The 2N107 was 1955. I have one or two of them:
The first JEDEC number was 2N34 in 1954:
I have at least one CK722, vintage 1953:
The CK718 was 1952:
The Bell Labs transistor is listed as the first, vintage 1951 (I was two =
years old):
Somewhere I have a four-lead metal can transistor labeled "U S Army" and = I=20 think it is a FET. If I find it I'll search for the number. Not sure how = old=20 it is. I got it in a "Poly-Packs" grab bag in the mid sixties.
Paul=20
On a sunny day (Thu, 15 Mar 2012 13:44:39 -0700) it happened Joerg wrote in :
Was nog God omnipresent?
That was before the animal lobby got active and shot Pim Fortuyn in front of the studio :-(
"By strange coincidence, in 2002 the most vocal and controversial Dutch 'Leefbaar Rotterdam' politician Pim Fortuyn was shot and killed by an animal rights activist at Hilversum Media Park just after finishing a radio interview.
I don't know of such a situation except perhaps two patents issued on the same claim, one reduced to practice, the other not.
And you never know with the patent examiners. I once had an application denied. I argued that the examiner was too dumb to understand the technology. Then it was approved ;-) ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
units
while
um and
=A0 =A0 =A0 =A0...Jim Thompson
LThink about it: if two people claim the same invention, for one to argue, in effect, that the invention is not really practicable, just because his rival never made a device that worked satisfactorily, will not help his cause. Presumably the fellow bringing the interference action has made the invention work, and expects to receive a great deal of income therefrom.
I suggest that you look at the drawings that were derived from actual construction. And there are at least three; reading them in order clearly shows that he knew what he was doing and had some understanding concerning use.
I dare say that the majority of patents up to 1935 (at least) had NO "photographic evidence".
I think the law states "someone SKILLED in the art", not "ordinary" person.
Link is not useful; even on high speed internet it takes too long and times out.
That would be very surprising. I do not mean that it has to be in the patent itself. When I was young and eager to build anyting I could get my hands on I looked for tube stuff. Because those were literally free, plucked from discarded TV sets. Some of the publications I used were pre-WW2 and they had pretty detailed photos in there. B/W and sometimes a bit grainy, of course, but lots. I can't imagine that he wouldn't have published if he had built a working prototype of a FET, doing its job inside some amplifier or a similar application. Or even just on the bench. Especially as a director of a research lab he should have been eager to publish. In those position that is kind of expected.
-- Regards, Joerg http://www.analogconsultants.com/
Not sure how or where he invented it but he worked in academic settings pretty much all his life. At an institute at Leipzig University in German and then after moving to the US he headed some big research lab over here. AFAIK he never worked in private industry.
Like the bumper sticker "Shit happens" that Forrest Gump invented? :-)
Yep. When people don't know how to put food on the table they sure won't be interested in some new product with a FET in there. An invention is only worth something if it can make a product more lucrative.
-- Regards, Joerg http://www.analogconsultants.com/
Reasonable point. I think (no research done) that he was not associated with any kind of a lab. It may be that his version of the FET was accidental and at home. Vulcanization of rubber was a home accident.. As far as selling (even the idea) goes, remember those times were in the muddle of the Depression and money was rather scarce to say the least.
al transistor from his patent?
Yes, Bell Labs did successfully. They kept quiet, no doubt to keep the publicity from detracting from their breakthrough, but the info was exposed in an old legal deposition from JB Johnson during the patenting. If you go track down the very first Bell Labs 1948 research paper on the transistor, there's also a paper in the same journal issue about their testing of a FET, but they carefully avoid saying this actually had been their test of Lilienfeld's patents. (This is why business is incompatible with science. When the research makes the business claims look bad, then the lies start spreading.)
Besides Stockman's report of a Lilienfeld transistor radio, the article below mentions a grad student B. Crawford in 1991 built successful but unstable Lilienfeld transistors for his dissertation, and in 1995 J. Ross built stable ones.
From Bell System Memorial site:
A fascinating letter to Wireless World in May 1981 under this title came from Dr Harry E. Stockman of Sercolab (Arlington, MA.) Then 76 years old, he had lived through the era under discussion and provided a valuable summary of "prior art" preceding the re-invention of the transistor. His letter had been triggered by a "Sixty Years Ago" item (in the same periodical) recalling an article by W. T. Ditcham on crystal oscillation in its May 1920 issue...
"Says Stockman, himself a distinguished author of many books and papers on semiconductor physics:
"(Lilienfeld) created his non-tube device around 1923, with one foot in Canada and the other in the USA, and the date of his Canadian patent application was October 1925. Later American patents followed, which should have been well known to the Bell Labs patent office. Lilienfeld demonstrated his remarkable tubeless radio receiver on many occasions, but God help a fellow who at that time threatened the reign of the tube.
----
Below is paraphrased from "The Other Transistor: early history of the MOSFET" See pp235-236:
In 1964 a physicist V. Bottom asked in Physics Today magazine whether Lilienfeld=92s transistors worked, and J. B. Johnson of Bell Labs responded saying that he=92d tested them and they didn=92t.
This then is probably the origin of the story that Lilienfeld never had any working hardware. An apparently trustworthy physicist (well known, of Johnson Noise fame) said so.
Then in 1995 R. G. Arns found a 1948 Bell Labs patent deposition by Johnson which said the opposite: that Bell Labs back then had a project to test Lilienfeld=92s transistors, and before Johnson took over the project, Shockely and Pearson had built a variation of Lilienfeld=92s aluminum oxide MOSFET from his patent and found only an 11% modulation index, but that "useful power output is substantial" ( ! ) And then they published a paper about this result. ( !! ) After Shockley/Pearson=92s success, Johnson had tested the other two Lilienfeld patents and was unable to replicate them =85so Johnson was only dishonest by omission, by covering up the fact that Bell Labs well knew that Lilienfeld had something real. Between these times B. Crawford in
1991 built successful but unstable Lilienfeld MOSFETs as his MS dissertation, and saw evidence that Lilienfeld must have built similar devices. In 1995 J. Ross built stable Lilienfeld MOSFETs. In addition to all this, a 1934 patent by Oskar Heil exists for another thin-film MOSFET.The author makes very telling statements about the honesty of these physicists:
"Published scientific, technical, and historical papers by these Bell scientists never mention either Lilienfeld=92s or Heil=92s prior work."
"Why =85 did Bell Laboratories personnel fail to acknowledge the earlier work of persons such as Lilienfeld and Heil? None of the Bell publications on transistors carries a reference to their work, not even the 1948 paper in which Shockley and Pearson demonstrated the field-effect experimentally. We also have J. B. Johnson=92s 1964 public response to Virgil Bottom compared to the admission contained in his
1949 affidavit filed in support of patent proceedings: the 1964 statement, by failing to mention Shockley and Pearson=92s 1948 confirmation of Lilienfeld=92s US Patent No. 1,900,018, appears to have been deliberately misleading. .The official history of the Bell System electronics work mentions Lilienfeld=92s and Heil=92s patents only in endnotes to a footnote. The footnote speaks of earlier patents which =91date back to the 1920s=92 and states that =91apparently all attempts to realise these concepts were futile[33]. In 1988, John Bardeen finally admitted that =91He [Lilienfeld] had the basic concept of controlling the flow of current in a semiconductor to make an amplifing devicee=94[34]. It seems possible that Shockley et al. had given up on the MOSFET idea due to surface problems; otherwise the admission, in Johnson=92s affidavit, that the Shockley and Pearson experiment corresponded to Lilienfeld=92s patent, would not have been so easy. It is also likely that they were silent and/or dismissive in their own publications and utterances in order to bolster their patent applications and to minimise challenges to their priority."----
One is led to wonder what the 1956 Nobel prize committee would have thought had they known that Lilienfeld had built a functioning pre-1940 transistor radio, and that Shockley had avoided referencing Lilienfeld=92s work in Shockley=92s 1948 paper announcing that Lilienfeld=92s FET transistors gave substantial gain.
transistor from his patent?
Thanks, Bill. Very interesting history lesson.
One puzzler though: If Lilienfeld really had a pre-1940 transistor radio and, as claimed, "demonstrated his remarkable tubeless radio receiver on many occasions" this begs some questions.
a. Where is that radio today? I can't imagine stuff like that just being tossed out.
b. Is there any photo of it? If not that would be highly unusual.
c. Is there a schematic of it? Drawings?
d. Was this published? I cannot imagine something like this not being published if it really happened and the radio worked.
-- Regards, Joerg http://www.analogconsultants.com/
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