Home |
Search |
Today's Posts |
#14
![]() |
|||
|
|||
![]()
In article , Leo
writes: This follows on the lines of the thread that Mike and I have commented on previously, so here goes: [continued from previous start - ] 6. Radio broadcasting would have become successful and tele- vision broadcasting even more so. "Overseas radiotelephone" would still exist via the first HF SSB radios in the 1930s. The first VHF FM mobiles would still be tested by various police Agreed - commercial and military radiocommunications would have grown anyway. Although some developments came from amateur radio, many more did not. A few years ago, I attended a Lucent course on their CDMA (spread spectrum, code division multiple access) cellular base station radio equipment. A Qualcomm engineer (CDMA is their patented technology) started off his presentation by asking us if we knew who invented the concept of CDMA. Bell Labs? MIT? The military? No. It was a German actress named Hedy Lamarr! She propsed it as a method of secret communications back in the 40s - obviously the technology (powerful computers) to implement it did not exist at the time. He went on to further amaze the group by informing us that she also devised the concept of frequency hopping (which I believe was used during the war - please correct me if I am wrong). Definitely a good thing that she got out of Germany prior to the war! Hedy was not an amateur, and had no interest in radio. That's been distorted from the original. IEEE Spectrum did a piece on Hedy's (Hedwig Markey is the name on the patent) and George Antheil's patent for a torpedo guidance device. Antheil was a friend of Hedy's and involved in automated pianos such as an updated player piano. Hedy had been married in Germany to a German industrialist who was a munitions maker; one of the products was a torpedo. Hedy wasn't a brainless actress and could grasp ideas. Antheil already had some inventions going in music and they traded some thoughts and concepts. Hedy had adopted the USA (or the other way around) and wanted to help the war effort any way she could (besides USO tours). The end result was an idea of a secure torpedo guidance system using programmable audio tones sent over a wire umbilical. It was doable with vacuum tube technology then. The patent was granted but never used by anyone! Eventually it expired. The USN and other nations using submarines and torpedos eventually developed wireline guidance of some torpedos but not with the system proposed by Markey and Antheil. For communications security, the USA already had AT&T to help in eventually developing a good voice scrambler so that the Germans lost their ability to eavesdrop on FDR's and Churchill's radiotelephone chats. That scrambler used shifting voice sub-bands and took up a small tow- behind trailer. Think of that as a parallel development in audio tone things. Hedy Lamarr inventing CDMA? I don't think so. The origin of that myth lies with some magazine or wire-service staffer who didn't know enough about electronic systems but probably saw a trade magazine article. Code Division Multiple Access is an eventual descendant of pulse-position modulation multiple voice channel radio relay equipment. The 8-voice-channel AN/TRC-6 that we signalmen in microwave radio relay school at Fort Monmouth used as a training system has much more in common to the eventual digitized voice comm systems than a torpedo guidance system. General Electric had already designed a 24-voice-channel microwave radio relay system for commercial use and that was purchased by the US Army. The later evolution of digital pulse trains in telephony circuits was a direct predecessor to CDMA. For that matter, the "rotor" encryption teleprinters of WW2 have more in common with CDMA. Those scrambled the teleprinter character code according to the rotor settings (actually multiple-pole rotary switches) to yield encryption without changing the basic nature of the 5-bit character code. The "Sigaba" of WW2 is an example, never compromised until the capture of the Pueblo years later. Spread- Spectrum techniques came out of work on developing encryption electronics along with Information Theory that had begun with things like "Shannon's Law" of 1948. Aligning a material object with an exceptionally beautiful woman of considerable intelligence is totally terrific PR. In truth, a stretch of the imagination that makes bungee cords break. Hedy and George came up with a TORPEDO GUIDANCE SYSTEM...that was never used as such. The original story has been told. Distortion came later. Good ideas come from everywhere. Absolutely. Even gorgeous actresses or handsome newsgroupies...:-) A question: what would not have been invented, or delayed, had the ARS not existed? Ham Radio Outlet, the chain, would never exist. :-) Newington, CT, would have a museum only of local artifacts. This and several other newsgroups would be about something entirely different...but just as concrete-headed in its patrons as the others. QSL card printers would have to go back to making picture postcards for sale at drug stores and supermarkets. TVI in urban neighborhoods would have a different flavor. Ed Hare might have to go out and work for a living... :-) The possibilities in any alternate universe are infinite. Everyone's ideas would be as "correct" as any other since there is nothing to base them on for "proof." :-) LHA / WMD |
Thread Tools | Search this Thread |
Display Modes | |
|
|