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#11
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It was the name given to the receiver end of the Baird
mechanical TV system, used by the BBC before Britland went out and started WWII. 30-line picture, transmitted in audio bandwidth. A similar scanning system appears (from the nature of the picture) to be used in some of the security cameras that rely on detecting bodily emissions. (Difficulty of getting a sensor that can work over the area of a pictur) Butch Magee wrote: Plod's Conscience wrote: My local garage is selling laser devices that project a straight line for just under a fiver. I wonder if these devices (with the lens removed so that they just produce a single spot) could be modulated to be the light source in a Baird Televisor? Also, I wonder what is the smallest such Televisor that has been produced? What a Televisor? KF5DE |
#12
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"superseded"
"quickly" " "Stookie". " What is quoted below is a disgraceful exhibition of the standards of schoolteachers and of L.I.A.R.s today. Perhaps it is no wonder that those who are candidates for the gangrenous degeneration that is the M3/CB Fools' Licence scheme have such difficulty in making any further progress, especially those who were either too lazy or too stupid to be able to tackle and then pass a Morse Code exam intended for 14-year-olds and had to wait until an exam targetted at 6-year-olds came along? Brian Reay wrote: The Baird system has been superceded by more modern techniques. In fact, unless you catch up quick, you may miss out a whole generation of technical improvements that have occured since "Stookie" |
#13
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![]() "Nedlar" wrote in message ... On Sat, 11 Mar 2006 15:58:41 -0600, Bob Bob wrote: For info only... John Logie Baird demonstrated colour TV in 1928. Coincidently, the year of your fiftieth birthday, IIRC. tox |
#14
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Played with it last night.
Powered as it is by AAA cells, it seems to have a greater power, and a greater reserve of power, than those laserpointers powered by watch batteries. Allowing for the lens that is used to produce the straight line beam, the spot from the end was easily picked out on a gravestone 1/4 mile away, thus suggesting that a tight beam is being produced. As these beasties come in a mounting that already has facilities for screw fixing, perhaps there is potential capability for optical communications? (Brian - in your experiments with the Fullerphone, you ran away from the question as to whether you crossed a property boundary, so.... 1. Did you cross a property boundary? 2. Why do you run away from this and so many other questions? 3. Is your attitude what we must all now expect from the RSCB?) Plod's Conscience wrote: My local garage is selling laser devices that project a straight line for just under a fiver. I wonder if these devices (with the lens removed so that they just produce a single spot) could be modulated to be the light source in a Baird Televisor? Also, I wonder what is the smallest such Televisor that has been produced? |
#15
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![]() What a Televisor? KF5DE .....it is a bit like an Interositer. |
#16
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![]() "Plod's Conscience" wrote in message oups.com... Played with it last night. Powered as it is by AAA cells, it seems to have a greater power, and a greater reserve of power, than those laserpointers powered by watch batteries. Given the relative size of AAA and "watch batteries", this is hardly surprising. Allowing for the lens that is used to produce the straight line beam, the spot from the end was easily picked out on a gravestone 1/4 mile away, thus suggesting that a tight beam is being produced. Laser's are coherent sources, the "ASER" stands for Amplification by Stimulated Emission of Radiation- the crucial phenomena in the operation of lasers and masers. The emitted photon is in phase with the stimulating photon. As these beasties come in a mounting that already has facilities for screw fixing, perhaps there is potential capability for optical communications? Been done. UK record, as of a couple of years back at least, was something like 75km. There is project in the latest RSGB handbook (if you are interesed I'll look up the page, I noticed the article but haven't read the detail). -- 73 Brian www.g8osn.org.uk |
#17
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![]() "Brian Reay" wrote in message ... "Plod's Conscience" wrote in message oups.com... Played with it last night. Powered as it is by AAA cells, it seems to have a greater power, and a greater reserve of power, than those laserpointers powered by watch batteries. Given the relative size of AAA and "watch batteries", this is hardly surprising. Allowing for the lens that is used to produce the straight line beam, the spot from the end was easily picked out on a gravestone 1/4 mile away, thus suggesting that a tight beam is being produced. Laser's are coherent sources, the "ASER" stands for Amplification by Stimulated Emission of Radiation- the crucial phenomena in the operation of lasers and masers. The emitted photon is in phase with the stimulating photon. As these beasties come in a mounting that already has facilities for screw fixing, perhaps there is potential capability for optical communications? Been done. UK record, as of a couple of years back at least, was something like 75km. There is project in the latest RSGB handbook (if you are interesed I'll look up the page, I noticed the article but haven't read the detail). Many years ago Practical Wireless had adesign for turning every ready torches (the ones with the big 9v batteries) into a transmitter and receiver by amplitude modulating the bulb. It actually worked (over about 20 feet). |
#18
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![]() "Gordon Hudson" wrote in message ... Been done. UK record, as of a couple of years back at least, was something like 75km. There is project in the latest RSGB handbook (if you are interesed I'll look up the page, I noticed the article but haven't read the detail). Many years ago Practical Wireless had adesign for turning every ready torches (the ones with the big 9v batteries) into a transmitter and receiver by amplitude modulating the bulb. It actually worked (over about 20 feet). Remember it (or one like it) well- it was one of the many projects I tried as a youngster. (Same sort of time I played with the Fuller Phone). With a laser pointer but I'm not sure how linear the transfer function is- ie is it linear enough to make AM viable. I've not looked into this but maybe someone will know. -- 73 Brian www.g8osn.org.uk |
#19
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![]() Brian Reay wrote: "Plod's Conscience" wrote Played with it last night. Perhaps he and Nedlar could get together; Nedlar didn't seem to have much to do last night either. Powered as it is by AAA cells, it seems to have a greater power, and a greater reserve of power, than those laserpointers powered by watch batteries. Given the relative size of AAA and "watch batteries", this is hardly surprising. Well, quite. The shortest Google search would have turned up the information needed to avoid him making such an obvious statement. A CR2032 battery has a capacity of 220 mAh at a current drain of 0.2 m/A.A modern AAA battery far exceeds that - I've left it as an exercise for the OP to search for that info.. Allowing for the lens that is used to produce the straight line beam, the spot from the end was easily picked out on a gravestone 1/4 mile away, thus suggesting that a tight beam is being produced. A 'tight beam' would indicate a spot not much larger than the laser source. Unfortunately, the lack of *any* objective statement in the above gives no indication that the beam was 'tight', merely that it reached it's target. Laser's are coherent sources, the "ASER" stands for Amplification by Stimulated Emission of Radiation- the crucial phenomena in the operation of lasers and masers. The emitted photon is in phase with the stimulating photon. As these beasties come in a mounting that already has facilities for screw fixing, perhaps there is potential capability for optical communications? Been done. UK record, as of a couple of years back at least, was something like 75km. There is project in the latest RSGB handbook (if you are interesed I'll look up the page, I noticed the article but haven't read the detail). Nothing new there with Gareth reinventing the wheel; it's very similar (perhaps part of the same syndrome?) to his continually re-writing history in his own vein. from Aero Spike |
#20
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Your underlying motivatiopn to pooh-pooh makes you
seem like a fool. It is the optical path that determines the divergence, or otherwise of the beam, by dispersion, diffraction, refraction mechanisms, and not the coherence of the radiation. (Cue rejoinder by Mrs.Nugatory, given 5 minutes or so, to look things up on google, to say that monochomatic radiation is unaffected by a dispersive medium.) Brian Reay wrote: "Plod's Conscience" wrote in message oups.com... Allowing for the lens that is used to produce the straight line beam, the spot from the end was easily picked out on a gravestone 1/4 mile away, thus suggesting that a tight beam is being produced. Laser's are coherent sources, the "ASER" stands for Amplification by Stimulated Emission of Radiation- the crucial phenomena in the operation of lasers and masers. The emitted photon is in phase with the stimulating photon. |
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