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#41
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:41:32 +0100, Eeyore
m wrote: BTW In the 50s or maybe 60s IIRC Ferranti invented 'virtual memory'. They sold the idea/patent to IBM. They were simply 40 or so years ahead of their time for mass usage. --- Since you're not the one turning the wheel of time, your saying that had they not come up with it when they did would have forced its development to be delayed by 40 years is just more of your ludicrous poppycock errrm... bull****. --- JF |
#42
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore
m wrote: And who broke the 'unbreakable' German Enigma code ? --- Actually, the Americans did, but for security reasons all of the records relating to that work were destroyed and all of the workers sworn to silence on pain of death. --- JF |
#43
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:41:32 +0100, Eeyore
m wrote: BTW In the 50s or maybe 60s IIRC Ferranti invented 'virtual memory'. They sold the idea/patent to IBM. They were simply 40 or so years ahead of their time for mass usage. http://en.wikipedia.org/wiki/Virtual_memory#History "Also, Burroughs independently released in 1961 the first commercial computer with virtual memory, the B5000,[5][6] which used segmentation rather than paging." The Wiki article doesn't mention Ferranti. Horrible idea anyhow. Virtual memory is the main contributor to poor data structure design and code bloat, not to mention things running about 20x slower than they should. Hour incredible nationalism is silly and largely wrong. John |
#44
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 15:46:49 +1000, Grant wrote:
On Sun, 05 Sep 2010 10:08:01 -0700, John Larkin wrote: On Sun, 05 Sep 2010 08:57:03 -0700, Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. I've actually seen schematics that used CHO for inductor, RLY for relay, LED for LED, POT or RV for a variable resistor, BR for a rectifier, CON for a connector. Audio, of course. Schematics that use such designators are invariably amateur crap circuits in their own right. They generally use the dreadful "4K7" thing too. Hey John, I get resistors marked 4k7 or 6R8. What's so bad about that? Not that I'd try to convince you otherwise, I got used to it about the same time a workplace talked me out of zigzag resistors and into box ones like the industry mags or something did. I just went with the flow, no point arguing. Though Farnell (your Newark too?) don't know the difference between upper and lower case multipliers, and MH might actually be uH or mH. Grant. We buy very little from Newark. They are a qualified supplier for just a few percent of the parts we buy, and mostly as a backup. The other distributors call on us often, with factory apps engineers in tow, flinging samples and dev boards all over the place, but Newark doesn't. John |
#45
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 09:20:33 -0500, John Fields
wrote: On Mon, 06 Sep 2010 01:47:41 +0100, Eeyore wrote: Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. What kind of equations do you use for calculating impedances ? For example Z = 2.pi.f.L is a common one. --- That's only true because: Z = sqrt (R² + (Xl - Xc)²) and it's the only circuit element being considered. More correctly, 2pi f L is considered to be the "inductive reactance" of an inductor, and the equation is written: Xl = 2pi f L --- L is clearly a well-understood 'shorthand' for inductance along with R and C for resistance and capacitance. I don't know of any components requiring designation on a schematic or PCB that require defining by Y, B or G, --- "Y" is the reference for any sort of resonator, but more particularly for the ubiquitous quartz crystal resonator. "B" is the reference designator for a blwer, motor, or synchro, and We use B for Battery. We use M for generic mechanical part. John |
#46
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:59:05 +0100, Eeyore
m wrote: ( some claim the war was shortened by between 2 and 4 years ) and it was us BRITISH who did it ! --- Did what? Claim the war was shortened by 2 to 4 years by Brits? Of course, what else did you expect, since you take credit for all the good stuff and blame the bad stuff on everybody else. --- JF |
#47
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:45:53 +0100, Eeyore
m wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. --- Since you don't have a clue about how much longer it would have taken to break the code had he not done what he did, when he did, you clearly have no business pretending to know what was relevant and what wasn't. --- JF |
#48
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 07:43:53 +0100, Eeyore
m wrote: John Fields wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore m wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. --- Us??? Sure. ANSI = American National Standards Institute. For the USA only. --- Nope, lots of folks use ANSI. Especially if they want to sell us something that we want to have meet a particular specification. As for the list, someone asked for a list of schematic reference designators, and I provided it. If you don't like it, tough ****; post your own list. --- Note AMERICAN. ANSI has no international validity. The rest of the world uses INTERNATIONAL standards like IEC. Why do you want to drag your feet against the tide ? --- Why would you think we do and, since we're members of the IEC, what makes you think that a lot of ANSI doesn't live in IEC standards? --- Answer ? You can't ! No-one cares about a small population of 300m people who insist on being irrelevant and backward. --- Fine talk coming from the mouth of a citizen of a pipsqueak third-world nanny state with a population of a paltry 61 million or so sheep trying to call the shots for the rest of the world by hiding behind the skirts of the Unites States of Europe. --- As for UL Electrical Standards, they have no alternative but to adopt IEC standards lest be locked out of the International market with silly amendments such as adopting your AWG wire sizes instead of mm2. --- You really don't know anything about UL, do you? --- You really should have 'metricated' ( as you said you would years ago ) to save such nonsence. --- Nonsense. --- JF |
#49
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 07:46:58 +0100, Eeyore
m wrote: John Fields wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyorwrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. --- With pleasure. :-) The reference designator assigned to a transistor: "Q", refers to (Q)uantum. From: http://www.pbs.org/transistor/science/info/quantum.html "Unlike water flowing along in one direction through a hose, electrons traveling along as electrical current can sometimes follow weird paths, especially if they're moving near the surface of a material. Moreover, electrons acting like a wave can sometimes burrow right through a barrier. Understanding this odd behavior of electrons was necessary as scientists tried to control how current flowed through the first transistors." Is this really any different from bizarre current flow in certain of your 'vacuum tubes' ? --- Well, yes, since a vacuum isn't quite the same thing as a single crystal. Which tubes are you talking about, BTW? --- JF |
#50
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 07:53:49 +0100, Eeyore
m wrote: (b) they most certainly went somewhere in due course. We were just way ahead of what the technology and materials technology of the time could offer. --- Well, then, I'm sure you'll have no trouble paying tribute to Alfred Gross and Chester Gould, American, for his vision of the cell phone ca 1946. --- JF |
#51
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 11:27:18 -0500, John Fields
wrote: On Mon, 06 Sep 2010 07:53:49 +0100, Eeyore wrote: (b) they most certainly went somewhere in due course. We were just way ahead of what the technology and materials technology of the time could offer. --- Well, then, I'm sure you'll have no trouble paying tribute to Alfred Gross and Chester Gould, American, for his vision of the cell phone ca 1946. --- JF Crikey! Stop feeding the Eeyore troll. Then he'd have no forum. ...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 | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Democrats are best served up prepared as a hash Otherwise the dogs will refuse to eat them |
#52
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:59:05 +0100, Eeyore
m wrote: Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer It's been rebuilt AIUI btw ! Futher info ...... Construction of a fully-functional replica[11] of a Colossus Mark 2 was undertaken by a team led by Tony Sale. In spite of the blueprints and hardware being destroyed, a surprising amount of material survived, mainly in engineers' notebooks, but a considerable amount of it in the U.S. The optical tape reader might have posed the biggest problem, but Dr. Arnold Lynch, its original designer, was able to redesign it to his own original specification. The reconstruction is on display, in the historically correct place for Colossus No. 9, at The National Museum of Computing, in H Block Bletchley Park in Milton Keynes, Buckinghamshire. In November 2007, to celebrate the project completion and to mark the start of a fundraising initiative for The National Museum of Computing, a Cipher Challenge[12] pitted the rebuilt Colossus against radio amateurs worldwide in being first to receive and decode three messages enciphered using the Lorenz SZ42 and transmitted from radio station DL0HNF in the Heinz Nixdorf MuseumsForum computer museum. The challenge was easily won by radio amateur Joachim Schüth, who had carefully prepared[13] for the event and developed his own signal processing and decrypt code using Ada.[14] The Colossus team were hampered by their wish to use World War II radio equipment,[15] delaying them by a day because of poor reception conditions. Nevertheless the victor's 1.4 GHz laptop, running his own code, took less than a minute to find the settings for all 12 wheels. The German codebreaker said: "My laptop digested ciphertext at a speed of 1.2 million characters per second—240 times faster than Colossus. If you scale the CPU frequency by that factor, you get an equivalent clock of 5.8 MHz for Colossus. That is a remarkable speed for a computer built in 1944."[16] The Cipher Challenge verified the successful completion of the rebuild project. "On the strength of today's performance Colossus is as good as it was six decades ago", commented Tony Sale. "We are delighted to have produced a fitting tribute to the people who worked at Bletchley Park and whose brainpower devised these fantastic machines which broke these ciphers and shortened the war by many months." ( some claim the war was shortened by between 2 and 4 years ) and it was us BRITISH who did it ! If the British had behaved sensibly, there would have been no war. John |
#53
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 09:00:39 -0700, Fred Abse
wrote: On Mon, 06 Sep 2010 06:45:53 +0100, Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer Colossus had nothing whatsoever to do with Enigma decryption. It was developed to assist decryption of the Lorenz cipher machine, a 5-bit teletype machine incorporating the modulo-2 addition of a pseudo-random stream. Used for high-level communications. To quote Tony Sale; "Fortunately, it was more pseudo than random". The machines used for finding the Enigma wheel settings were purely electromechanical. They were called Bombes. One of those has been replicated, too. Eeyore is so rah-rah British he has to make up accomplishments. Serious inferiority complex. Poor fact checking. John |
#54
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ANSI reference designators - ANSI reference designators.pdf
Eeyore wrote: Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer It's been rebuilt AIUI btw ! Futher info ...... Construction of a fully-functional replica[11] of a Colossus Mark 2 was undertaken by a team led by Tony Sale. In spite of the blueprints and hardware being destroyed, a surprising amount of material survived, mainly in engineers' notebooks, but a considerable amount of it in the U.S. The optical tape reader might have posed the biggest problem, but Dr. Arnold Lynch, its original designer, was able to redesign it to his own original specification. The reconstruction is on display, in the historically correct place for Colossus No. 9, at The National Museum of Computing, in H Block Bletchley Park in Milton Keynes, Buckinghamshire. Who cares? Or is that the highest level computer design has reached in 'Blighty'? -- Politicians should only get paid if the budget is balanced, and there is enough left over to pay them. |
#55
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ANSI reference designators - ANSI reference designators.pdf
Eeyore wrote: John Fields wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore m wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. --- Us??? Sure. ANSI = American National Standards Institute. For the USA only. Of course. We don't want dumb asses like you polluting a real standard. -- Politicians should only get paid if the budget is balanced, and there is enough left over to pay them. |
#56
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ANSI reference designators - ANSI reference designators.pdf
John Larkin wrote: On Mon, 06 Sep 2010 06:59:05 +0100, Eeyore m wrote: Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer It's been rebuilt AIUI btw ! Futher info ...... Construction of a fully-functional replica[11] of a Colossus Mark 2 was undertaken by a team led by Tony Sale. In spite of the blueprints and hardware being destroyed, a surprising amount of material survived, mainly in engineers' notebooks, but a considerable amount of it in the U.S. The optical tape reader might have posed the biggest problem, but Dr. Arnold Lynch, its original designer, was able to redesign it to his own original specification. The reconstruction is on display, in the historically correct place for Colossus No. 9, at The National Museum of Computing, in H Block Bletchley Park in Milton Keynes, Buckinghamshire. In November 2007, to celebrate the project completion and to mark the start of a fundraising initiative for The National Museum of Computing, a Cipher Challenge[12] pitted the rebuilt Colossus against radio amateurs worldwide in being first to receive and decode three messages enciphered using the Lorenz SZ42 and transmitted from radio station DL0HNF in the Heinz Nixdorf MuseumsForum computer museum. The challenge was easily won by radio amateur Joachim Schüth, who had carefully prepared[13] for the event and developed his own signal processing and decrypt code using Ada.[14] The Colossus team were hampered by their wish to use World War II radio equipment,[15] delaying them by a day because of poor reception conditions. Nevertheless the victor's 1.4 GHz laptop, running his own code, took less than a minute to find the settings for all 12 wheels. The German codebreaker said: "My laptop digested ciphertext at a speed of 1.2 million characters per second—240 times faster than Colossus. If you scale the CPU frequency by that factor, you get an equivalent clock of 5.8 MHz for Colossus. That is a remarkable speed for a computer built in 1944."[16] The Cipher Challenge verified the successful completion of the rebuild project. "On the strength of today's performance Colossus is as good as it was six decades ago", commented Tony Sale. "We are delighted to have produced a fitting tribute to the people who worked at Bletchley Park and whose brainpower devised these fantastic machines which broke these ciphers and shortened the war by many months." ( some claim the war was shortened by between 2 and 4 years ) and it was us BRITISH who did it ! If the British had behaved sensibly, there would have been no war. Including Iraq. -- Politicians should only get paid if the budget is balanced, and there is enough left over to pay them. |
#57
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ANSI reference designators - ANSI reference designators.pdf
John Larkin wrote: On Mon, 06 Sep 2010 09:00:39 -0700, Fred Abse wrote: On Mon, 06 Sep 2010 06:45:53 +0100, Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer Colossus had nothing whatsoever to do with Enigma decryption. It was developed to assist decryption of the Lorenz cipher machine, a 5-bit teletype machine incorporating the modulo-2 addition of a pseudo-random stream. Used for high-level communications. To quote Tony Sale; "Fortunately, it was more pseudo than random". The machines used for finding the Enigma wheel settings were purely electromechanical. They were called Bombes. One of those has been replicated, too. Eeyore is so rah-rah British he has to make up accomplishments. Serious inferiority complex. Poor fact checking. We should call him Mr. Checkov. -- Politicians should only get paid if the budget is balanced, and there is enough left over to pay them. |
#58
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 11:01:00 -0500, John Fields
wrote: On Mon, 06 Sep 2010 07:43:53 +0100, Eeyore wrote: John Fields wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore m wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. --- Us??? Sure. ANSI = American National Standards Institute. For the USA only. --- Nope, lots of folks use ANSI. Especially if they want to sell us something that we want to have meet a particular specification. As for the list, someone asked for a list of schematic reference designators, and I provided it. If you don't like it, tough ****; post your own list. I'd imagine it would go something like UDC unidirectional RCA cable TWK Tweak, the felt-covered brick you put on top of transformers to improve soundstaging CSL capacitor, silver foil X $1500 secret quantum mechanical electron organizer PCB Power cable, burned in VR Vishay resistor CB Black Beauty capacitor V$$ $450 original Western Electric 300B vacuum tube http://en.wikipedia.org/wiki/300B John |
#59
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ANSI reference designators - ANSI reference designators.pdf
John Larkin wrote in
: On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore m wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. That is the most stupid comment I've heard in the last 60 years. |
#60
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 17:31:39 GMT, Bob Quintal
wrote: John Larkin wrote in : On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore m wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. That is the most stupid comment I've heard in the last 60 years. "Electricity" is about moving power around. "Electronics" is about using electricity to process information. You can't do much of that without a fast gain element. Wiki agrees with me that electronics really began with the invention of the triode: http://en.wikipedia.org/wiki/Electronics One can argue definitions, but I don't think you can do "electronics" with just Fleming diodes, which are really Edison diodes. Electronics exploded into existence with DeForest's invention of the triode. John |
#61
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 17:31:39 GMT, Bob Quintal
wrote: John Larkin wrote in : On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore m wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. That is the most stupid comment I've heard in the last 60 years. Consider the source. ...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 | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Democrats are best served up prepared as a hash Otherwise the dogs will refuse to eat them |
#62
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 09:20:33 -0500, John Fields wrote:
On Mon, 06 Sep 2010 01:47:41 +0100, Eeyore wrote: Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. What kind of equations do you use for calculating impedances ? For example Z = 2.pi.f.L is a common one. --- That's only true because: Z = sqrt (R² + (Xl - Xc)²) and it's the only circuit element being considered. More correctly, 2pi f L is considered to be the "inductive reactance" of an inductor, and the equation is written: Xl = 2pi f L --- L is clearly a well-understood 'shorthand' for inductance along with R and C for resistance and capacitance. I don't know of any components requiring designation on a schematic or PCB that require defining by Y, B or G, --- "Y" is the reference for any sort of resonator, but more particularly for the ubiquitous quartz crystal resonator. "B" is the reference designator for a blwer, motor, or synchro, and "G" is the reference designator for, among other things, a generator. Saw G1 for a overvoltage phone line protector (Gas discharge?) recently. Grant. |
#63
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 08:12:55 -0700, John Larkin wrote:
On Mon, 06 Sep 2010 15:46:49 +1000, Grant wrote: On Sun, 05 Sep 2010 10:08:01 -0700, John Larkin wrote: On Sun, 05 Sep 2010 08:57:03 -0700, Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. I've actually seen schematics that used CHO for inductor, RLY for relay, LED for LED, POT or RV for a variable resistor, BR for a rectifier, CON for a connector. Audio, of course. Schematics that use such designators are invariably amateur crap circuits in their own right. They generally use the dreadful "4K7" thing too. Hey John, I get resistors marked 4k7 or 6R8. What's so bad about that? Not that I'd try to convince you otherwise, I got used to it about the same time a workplace talked me out of zigzag resistors and into box ones like the industry mags or something did. I just went with the flow, no point arguing. Though Farnell (your Newark too?) don't know the difference between upper and lower case multipliers, and MH might actually be uH or mH. Grant. We buy very little from Newark. They are a qualified supplier for just a few percent of the parts we buy, and mostly as a backup. The other distributors call on us often, with factory apps engineers in tow, flinging samples and dev boards all over the place, but Newark doesn't. Fair enough, I'm not production buying, so it's a long time since I had sales people call, and in the '80s the latest databooks were about all they offered for free Though National Semi had a great Applications Engineer for a while, used to run some hairy analog problems by him at times. Over here we got two companies selling without minimum order and with free delivery, Farnell and RS Comp., both UK based. Your (US) popular DigiKey has flat rate US$30 delivery fee to AU and a free call line, but it's difficult for me to justify using that for prototype quantities. Grant. |
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ANSI reference designators - ANSI reference designators.pdf
John Larkin wrote: On Mon, 06 Sep 2010 12:47:38 -0400, "Michael A. Terrell" wrote: Eeyore wrote: John Fields wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore m wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. --- Us??? Sure. ANSI = American National Standards Institute. For the USA only. Given a choice between ignoring ANSI standards and ignoring IEC standards, the US ones are much better. Ever tried to read the CE stuff? Nightmare. That's why Eeyore likes it. It reminds him of Lucas. -- Politicians should only get paid if the budget is balanced, and there is enough left over to pay them. |
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 01:56:50 +0100, Eeyore
m wrote: Grant wrote: On Sun, 05 Sep 2010 07:11:20 +0100, Eeyore m wrote: Phil Hobbs wrote: Eeyore wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. Graham Chronological snobbery. I thought it was Brits who liked to keep old names for things, such as your treasury department, which is still named after the gingham tablecloth that they used to count the money on, around a thousand years ago. (*) The name Treasury ( which one could critice itself for being 'old-fashioned' despite common US usage ) has no connection with tablecloths. You ought to do your research before posting. http://www.hm-treasury.gov.uk/about_history.htm " The origin of the name “exchequer” derives from the chequered table (based on the abacus) which was used from about 1110 for calculating expenditure and receipts. " British English btw is renowned for accepting many forms of linguistic influence inluding taking entire foreign phrases into common use. In this respect it is probably the most dynamic language in the world. Now explain why U = integrated circuit and Q = transistor. It defies any form of common sense. Sensible usage is 'IC' and 'TR'. So the transformer is? Typically TX is my experience. I and C already taken for other uses, so remaining letters get a showing too. Too hard? Hardly matters. Where on a schematic do you come across an 'I' ? Not terribly common, but indicator and not always lamps. IC is a combination of 2 leters so clearly distinguishable. Graham |
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 01:48:56 +0100, Eeyore
m wrote: John Larkin wrote: On Sun, 05 Sep 2010 08:57:03 -0700, Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. I've actually seen schematics that used CHO for inductor, RLY for relay, LED for LED, POT or RV for a variable resistor, BR for a rectifier, CON for a connector. Audio, of course. Schematics that use such designators are invariably amateur crap circuits in their own right. They generally use the dreadful "4K7" thing too. John Not happy with posting it once ? Internet service is weird up here in the mountains. John |
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ANSI reference designators - ANSI reference designators.pdf
On Tue, 07 Sep 2010 22:08:05 GMT, Bob Quintal
wrote: John Larkin wrote in : On Mon, 06 Sep 2010 17:31:39 GMT, Bob Quintal wrote: John Larkin wrote in : On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore m wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. That is the most stupid comment I've heard in the last 60 years. "Electricity" is about moving power around. "Electronics" is about using electricity to process information. You can't do much of that without a fast gain element. Not much but some. Take for example the Detection and demodulation of an audio signal using only a diode and a high impedance voltage to sound transducer. Wiki agrees with me that electronics really began with the invention of the triode: http://en.wikipedia.org/wiki/Electronics That article also says "Some common electronic components are capacitors, resistors, diodes, transistors, etc." .......................^^^^^^ The argument is philosophical. Both the Edison effect and the Fleming tube were novelties. The Audion changed the world. John |
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 06:41:32 +0100, Eeyore
m wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore wrote: John Larkin wrote: Americans invented electronics, invented modern electronics, invented the vacuum triode, the opamp, the transistor, the IC, semiconductor RAM, uPs, LEDs, lasers, programmable logic, all sorts of stuff. We picked the reference designators, because we needed them first. Just checking, you're wrong about the LED too. http://en.wikipedia.org/wiki/Light-e..._early_devices Electroluminescence was discovered in 1907 by the British experimenter H. J. Round of Marconi Labs, using a crystal of silicon carbide and a cat's-whisker detector.[4][5] Russian Oleg Vladimirovich Losev independently reported on the creation of an LED in 1927. Neither want anywhere. I assume you meant 'went' rather than 'want' ? At the time there was no practical use. Doesn't change the date of discovery though. SiC too ! That took a while to enter general LED usage. Accidental discoveries that result in no practical application are not just useless, they suggest a lack of insight. LEDs were, like transistors, developed in the USA deliberately, by people who understood solid-state physics and knew, or at least suspected, that the devices were possible. The team at Bell Labs was specifically looking for an amplification mechanism in germanium, and just happened to find the wrong one (they had theorized the jfet) which changed the world. The RadLab scientists had suggested that a semiconductor triode was possible. http://en.wikipedia.org/wiki/Led#History The most notable recent British contribution to electronics may be the ARM processor architecture, which has a good shot at killing x86. John |
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ANSI reference designators - ANSI reference designators.pdf
On Sun, 05 Sep 2010 19:38:30 -0700, John Larkin
wrote: On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. BTW do you also dismiss the work of Marconi ? It wasn't electronics either. http://en.wikipedia.org/wiki/Radio#History John You picked this fight JL. |
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 09:38:55 -0700, John Larkin
wrote: On Mon, 06 Sep 2010 09:00:39 -0700, Fred Abse wrote: On Mon, 06 Sep 2010 06:45:53 +0100, Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer Colossus had nothing whatsoever to do with Enigma decryption. It was developed to assist decryption of the Lorenz cipher machine, a 5-bit teletype machine incorporating the modulo-2 addition of a pseudo-random stream. Used for high-level communications. To quote Tony Sale; "Fortunately, it was more pseudo than random". The machines used for finding the Enigma wheel settings were purely electromechanical. They were called Bombes. One of those has been replicated, too. Eeyore is so rah-rah British he has to make up accomplishments. Serious inferiority complex. Poor fact checking. John Very much like you. |
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ANSI reference designators - ANSI reference designators.pdf
On Mon, 06 Sep 2010 01:53:22 +0100, Eeyore
m wrote: John Larkin wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore m wrote: John Fields wrote: ANSI reference designators.pdf Only for antiquated Americans of course. Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. We invented them, we named them. You can have credit for "V". Actually the first transistor ( a FET ) was theorised by a German in the 30s IIRC. I believe he even tried to make one but materials weren't pure enough back then. Nope. 1920s by Japanese. I went looking for references but many search engines don't have anything over 50 years old. Similarly a Briton forsaw ICs in the 50s calling them 'solid circuits' at the time. Graham |
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ANSI reference designators - ANSI reference designators.pdf
On Wed, 08 Sep 2010 03:57:18 -0700,
wrote: On Sun, 05 Sep 2010 19:38:30 -0700, John Larkin wrote: On Mon, 06 Sep 2010 02:28:56 +0100, Eeyore m wrote: John Larkin wrote: Americans invented electronics WRONG ! Never mind the early work of Faraday, Fleming et al, The first 'electronic' device, the diode, was invented by a Briton. http://en.wikipedia.org/wiki/Diode http://en.wikipedia.org/wiki/Frederick_Guthrie I don't consider Fleming's diode to quite be "electronics" because it didn't have gain. BTW do you also dismiss the work of Marconi ? It wasn't electronics either. http://en.wikipedia.org/wiki/Radio#History John You picked this fight JL. Fight? I stated what I "don't consider" to quite be electronics. Feel free to consider whatever you want. Is a flashlight electronics? A kerosene lantern? A spark gap/coherer link? Believe what you will. John |
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ANSI reference designators - ANSI reference designators.pdf
On Wed, 08 Sep 2010 04:15:51 -0700,
wrote: On Mon, 06 Sep 2010 09:38:55 -0700, John Larkin wrote: On Mon, 06 Sep 2010 09:00:39 -0700, Fred Abse wrote: On Mon, 06 Sep 2010 06:45:53 +0100, Eeyore wrote: John Larkin wrote: On Mon, 06 Sep 2010 03:00:38 +0100, Eeyore m wrote: And who broke the 'unbreakable' German Enigma code ? http://www.bletchleypark.org.uk/ This guy? http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w "Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II." Clearly not immediately relevant since it was much later that the German Enigma code was broken. How much did he contribute to this .... http://en.wikipedia.org/wiki/Colossus_computer Colossus had nothing whatsoever to do with Enigma decryption. It was developed to assist decryption of the Lorenz cipher machine, a 5-bit teletype machine incorporating the modulo-2 addition of a pseudo-random stream. Used for high-level communications. To quote Tony Sale; "Fortunately, it was more pseudo than random". The machines used for finding the Enigma wheel settings were purely electromechanical. They were called Bombes. One of those has been replicated, too. Eeyore is so rah-rah British he has to make up accomplishments. Serious inferiority complex. Poor fact checking. John Very much like you. Be a jerk. Or post some electronics. Take your pick. John |
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ANSI reference designators - ANSI reference designators.pdf
On Thu, 09 Sep 2010 01:25:05 -0700 Fred Abse
wrote in Message id: : On Mon, 06 Sep 2010 12:48:41 -0400, Michael A. Terrell wrote: We should call him Mr. Checkov. More likely Mr. Dzherkov. Okay, now *that* was funny! |
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ANSI reference designators - ANSI reference designators.pdf
On Thu, 09 Sep 2010 01:25:02 -0700, Fred Abse
wrote: On Sun, 05 Sep 2010 15:25:57 -0700, John Larkin wrote: Schematics that use such designators are invariably amateur crap circuits in their own right. They generally use the dreadful "4K7" thing too. The "4k7" thing is not entirely without merit. Have you never encountered a badly reproduced, or hand drawn schematic, where decimal points are either missing, or produced by artifacts of the repro process? I took engineering drawing in college, and they forced us to learn to draw good digits and decimal points. Physicists and architects and rocket scientists seem to manage to use decimal points properly. "4k7" screams amateur audio. SI unit designations don't look like that. "IC1" and "TR9" look amateur, too. I recall wasting a lot of time on a problem where a resistor, apparently 51 ohm, should have been 5.1 ohm. Faxed (thermal) schematic, not obvious from context. Thermal fax? When? 5 1 should give you a hint that it's not 51. I've recently seen a hand-drawn 4k7 that looked like 457. John |
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ANSI reference designators - ANSI reference designators.pdf
John Fields wrote:
On Mon, 06 Sep 2010 01:47:41 +0100, Eeyore m wrote: Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. What kind of equations do you use for calculating impedances ? For example Z = 2.pi.f.L is a common one. --- That's only true because: Z = sqrt (R² + (Xl - Xc)²) and it's the only circuit element being considered. More correctly, 2pi f L is considered to be the "inductive reactance" of an inductor, and the equation is written: Xl = 2pi f L --- L is clearly a well-understood 'shorthand' for inductance along with R and C for resistance and capacitance. I don't know of any components requiring designation on a schematic or PCB that require defining by Y, B or G, --- "Y" is the reference for any sort of resonator, but more particularly for the ubiquitous quartz crystal resonator. "B" is the reference designator for a blwer, motor, or synchro, and "G" is the reference designator for, among other things, a generator. In the USA only. Graham |
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ANSI reference designators - ANSI reference designators.pdf
On Fri, 10 Sep 2010 12:19:22 +0100, Eeyore
m wrote: John Fields wrote: On Mon, 06 Sep 2010 01:47:41 +0100, Eeyore m wrote: Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. What kind of equations do you use for calculating impedances ? For example Z = 2.pi.f.L is a common one. --- That's only true because: Z = sqrt (R² + (Xl - Xc)²) and it's the only circuit element being considered. More correctly, 2pi f L is considered to be the "inductive reactance" of an inductor, and the equation is written: Xl = 2pi f L --- L is clearly a well-understood 'shorthand' for inductance along with R and C for resistance and capacitance. I don't know of any components requiring designation on a schematic or PCB that require defining by Y, B or G, --- "Y" is the reference for any sort of resonator, but more particularly for the ubiquitous quartz crystal resonator. "B" is the reference designator for a blwer, motor, or synchro, and "G" is the reference designator for, among other things, a generator. In the USA only. --- Got a list of IEC reference designations? --- JF |
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ANSI reference designators - ANSI reference designators.pdf
On Fri, 10 Sep 2010 12:19:22 +0100, Eeyore
m wrote: John Fields wrote: On Mon, 06 Sep 2010 01:47:41 +0100, Eeyore m wrote: Fred Abse wrote: On Sat, 04 Sep 2010 07:56:51 +0100, Eeyore wrote: Do please especially explain the relevance of the letter Q to indicate a transistor or U for an IC. No sillier than "L" for inductance, or "Z" for impedance, or "Y" for admittance, or "B" for susceptance, or "G" for conductance. What kind of equations do you use for calculating impedances ? For example Z = 2.pi.f.L is a common one. --- That's only true because: Z = sqrt (R² + (Xl - Xc)²) and it's the only circuit element being considered. More correctly, 2pi f L is considered to be the "inductive reactance" of an inductor, and the equation is written: Xl = 2pi f L --- L is clearly a well-understood 'shorthand' for inductance along with R and C for resistance and capacitance. I don't know of any components requiring designation on a schematic or PCB that require defining by Y, B or G, --- "Y" is the reference for any sort of resonator, but more particularly for the ubiquitous quartz crystal resonator. "B" is the reference designator for a blwer, motor, or synchro, and "G" is the reference designator for, among other things, a generator. In the USA only. Graham Post a real schematic of something you've designed. John |
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ANSI reference designators - ANSI reference designators.pdf
"John Larkin" wrote in message
... I took engineering drawing in college, and they forced us to learn to draw good digits and decimal points. Physicists and architects and rocket scientists seem to manage to use decimal points properly. My understanding was that, regardless of how good your decimal points were, by virtue or being physically small, in the process of Xeroxing and just regular old wear and tear on the paper, sooner or later the decimal points would tend to be lost, and *that* was the main impetus for "4k7" -- along with the fact that even the the lowest-scording graduate in your class still went out and got to put on an "engineer" cap. Now that schematics are seldom Xeroxed and likely viewed as or more often on a screen than on paper, I don't think the motivation really remains. When I went to school EEs didn't take engineering drawing anymore, although MEs still did. By now I expect their classes are all using SolidWorks or AutoCAD or similar. "4k7" screams amateur audio. To me they just scream, "designed in Europe." :-) SI unit designations don't look like that. "IC1" and "TR9" look amateur, too. I'm looking at a circuit board made by JVC here that uses "IC1" for big ICs (like microcontrollers) -- although still "U1" for, e.g., regulators --, "CON1" (connectors), "ESDA1" (little ESD-handling diode arrays), "JP1" (jumpers) and "CN1" (also a connector -- not sure how it's different from the "CON1" connectors). You can add them to your list of places you'd prefer not to work at. :-) ---Joel |
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ANSI reference designators - ANSI reference designators.pdf
On Fri, 10 Sep 2010 11:06:37 -0700, "Joel Koltner"
wrote: "John Larkin" wrote in message .. . I took engineering drawing in college, and they forced us to learn to draw good digits and decimal points. Physicists and architects and rocket scientists seem to manage to use decimal points properly. My understanding was that, regardless of how good your decimal points were, by virtue or being physically small, in the process of Xeroxing and just regular old wear and tear on the paper, sooner or later the decimal points would tend to be lost, and *that* was the main impetus for "4k7" -- along with the fact that even the the lowest-scording graduate in your class still went out and got to put on an "engineer" cap. Now that schematics are seldom Xeroxed and likely viewed as or more often on a screen than on paper, I don't think the motivation really remains. When I went to school EEs didn't take engineering drawing anymore, although MEs still did. By now I expect their classes are all using SolidWorks or AutoCAD or similar. "4k7" screams amateur audio. To me they just scream, "designed in Europe." :-) SI unit designations don't look like that. "IC1" and "TR9" look amateur, too. I'm looking at a circuit board made by JVC here that uses "IC1" for big ICs (like microcontrollers) -- although still "U1" for, e.g., regulators --, "CON1" (connectors), "ESDA1" (little ESD-handling diode arrays), "JP1" (jumpers) and "CN1" (also a connector -- not sure how it's different from the "CON1" connectors). One division of GE just used a number. A resistor might be 12, a transistor 43. That's the opposite extreme. You can add them to your list of places you'd prefer not to work at. :-) ---Joel Yup. The audio people tend to be like that, way out of the mainstream of rational electronic design. They tend to fiddle with bizarre circuits until some big-shot's hearing-damaged subjective response is satisfied. There's a lot of superstitious learning involved. And a lot of plain BS. The other problem with audio is that the engineers tend to be flunkies, with the business types and "the artists" being the superstars. There are places where the engineers are the stars, which are more fun to work at. John |
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