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cycles to hertz - when?
Watching the Eddie Izzard film on the development of radar, I was
surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? |
cycles to hertz - when?
"S Viemeister" wrote in message ... Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? Nope, they stuffed that detail up. |
cycles to hertz - when?
After serious thinking S Viemeister wrote :
Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? No - I don't know exactly when things changed, but I think the change was gradual between 1960 and 1970. |
cycles to hertz - when?
On Friday, February 1, 2019 at 1:33:02 AM UTC, S Viemeister wrote:
Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? It's Megacycles per second anyway - mc is meanlingless without a time element. On SW radio in the 60's it was mainly wavelengths in metres that was used, then Mc/s and Kc/s and then kiloHertz and MegaHertz came in more and more during the 1970's. |
cycles to hertz - when?
Not really.
It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Brian -- ----- -- This newsgroup posting comes to you directly from... The Sofa of Brian Gaff... Blind user, so no pictures please Note this Signature is meaningless.! "S Viemeister" wrote in message ... Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? |
cycles to hertz - when?
One thing that has always interested me is the fact that many shortwave
stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. I often wonder why we have still got the two. Metres is of course very handy if you want to make your own aerial, but then you have this adjustment for the velocity factor for conductors. However I notice that when you get to really high frequencies they are termed milimetric wavelengths. By the time the wavelength nears that of light we use other terms to describe the frequency. Basically though the energy received at a point in a given time period has to be greater the higher the frequency. The wave particle duality still makes radiation of photons very interesting to me. One of the reasons I still tune the short wave bands even though in most cases I could get the same thing on the internet is that it means that a certain set of photons travels over a very random route from the transmitting aerial to mine. Oh and as somebody why has experienced an RF burn. touching a transmitting aerial is definitely not a good thing to do. Brian -- ----- -- This newsgroup posting comes to you directly from... The Sofa of Brian Gaff... Blind user, so no pictures please Note this Signature is meaningless.! wrote in message ... On Friday, February 1, 2019 at 1:33:02 AM UTC, S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? It's Megacycles per second anyway - mc is meanlingless without a time element. On SW radio in the 60's it was mainly wavelengths in metres that was used, then Mc/s and Kc/s and then kiloHertz and MegaHertz came in more and more during the 1970's. |
cycles to hertz - when?
Brian Gaff presented the following explanation :
One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres = 299792.458/ kHz kHz = 299792.458/ metres |
cycles to hertz - when?
|
cycles to hertz - when?
On Fri, 01 Feb 2019 08:46:54 GMT, Harry Bloomfield
wrote: Brian Gaff presented the following explanation : One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres = 299792.458/ kHz kHz = 299792.458/ metres I thought it was 300,000. The teaching at my school must have been a bit rubbish! |
cycles to hertz - when?
On 01/02/2019 09:23, Scott wrote:
On Fri, 01 Feb 2019 08:46:54 GMT, Harry Bloomfield wrote: Brian Gaff presented the following explanation : One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres = 299792.458/ kHz kHz = 299792.458/ metres I thought it was 300,000. The teaching at my school must have been a bit rubbish! Fings are more akrut now |
cycles to hertz - when?
On 01/02/2019 08:15, Brian Gaff wrote:
Not really. It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Brian I don't know - Hums, kHum, MHum, GHum and Thum are not so bad. 50Hum describes mains hum very accuratly! |
cycles to hertz - when?
On Friday, 1 February 2019 01:33:02 UTC, S Viemeister wrote:
Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? It's c/s not cycles. (cycles per second) If you leave the time element out, it's meaningless. https://en.wikipedia.org/wiki/Hertz |
cycles to hertz - when?
On 01/02/2019 08:46, Harry Bloomfield wrote:
Brian Gaff presented the following explanation : One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. *Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres =*** 299792.458/ kHz kHz =* 299792.458/ metres ....in a vacuum. I await with interest the essay on the conversion factor for BBC long wave from Droitwich :) -- Robin reply-to address is (intended to be) valid |
cycles to hertz - when?
On Friday, February 1, 2019 at 8:15:19 AM UTC, Brian Gaff wrote:
Not really. It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Or even this chap: https://en.wikipedia.org/wiki/August_Kundt |
cycles to hertz - when?
On 01/02/2019 09:32, Halmyre wrote:
On Friday, February 1, 2019 at 8:15:19 AM UTC, Brian Gaff wrote: Not really. It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Or even this chap: https://en.wikipedia.org/wiki/August_Kundt Trump is a MKundt! |
cycles to hertz - when?
On 01/02/2019 09:32, Halmyre wrote:
On Friday, February 1, 2019 at 8:15:19 AM UTC, Brian Gaff wrote: Or even this chap: https://en.wikipedia.org/wiki/August_Kundt The physics master at my (Catholic) grammar school always referred to it as "That tube". Another Dave -- Change nospam to techie |
cycles to hertz - when?
"Harry Bloomfield" wrote in message ... After serious thinking S Viemeister wrote : Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? No - I don't know exactly when things changed, but I think the change was gradual between 1960 and 1970. It never changed for me ...... |
cycles to hertz - when?
On 01/02/2019 08:15, Brian Gaff wrote:
Not really. It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Brian It could easily have been a Rutherford. He was an early pioneer of radio transmission and receiving but was persuaded that it would never amount to much and Marconi was to his disappointment was slightly ahead. https://en.wikipedia.org/wiki/Ernest..._and_education Instead he went on to investigate the new field of radioactivity for which research he is much more famous. -- Regards, Martin Brown |
cycles to hertz - when?
On Fri, 01 Feb 2019 10:14:32 +0000, Martin Brown wrote:
It could easily have been a Rutherford. He was an early pioneer of radio transmission and receiving but was persuaded that it would never amount to much and Marconi was to his disappointment was slightly ahead. I always think of this story (perfectly true; I was part of the conversation). I know the Darwin family quite well because one of the University of Kent Colleges is named after Charles Darwin. I was talking to the oldest member of the family a few years ago, and he was saying that he actually felt an affinity with three of the Colleges - Darwin, Keynes and Eliot. I knew about the Darwin family being closely connected with, and intermarrying with, the Keynes family (which I also know, because of that). So I asked him why he felt an affinity with Rutherford. "Oh", said he. "Ernest was my godfather". -- My posts are my copyright and if @diy_forums or Home Owners' Hub wish to copy them they can pay me £1 a message. Use the BIG mirror service in the UK: http://www.mirrorservice.org *lightning surge protection* - a w_tom conductor |
cycles to hertz - when?
Scott used his keyboard to write :
I thought it was 300,000. The teaching at my school must have been a bit rubbish! Yes, it used to be, but it slowed down over time lol |
cycles to hertz - when?
On 01/02/2019 01:32, S Viemeister wrote:
Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? No. -- "And if the blind lead the blind, both shall fall into the ditch". Gospel of St. Mathew 15:14 |
cycles to hertz - when?
On 01/02/2019 09:26, Andy Bennet wrote:
On 01/02/2019 09:23, Scott wrote: I thought it was 300,000.Â* The teaching at my school must have been a bit rubbish! Fings are more akrut now Do you mean that pi is not 22/7. A lot of exam questions had the 22 and 7, to be cancelled out by pi. -- mailto : news {at} admac {dot} myzen {dot} co {dot} uk |
cycles to hertz - when?
I blame that Dutch firm, Hertz Van Rentals myself...:-)
Brian -- ----- -- This newsgroup posting comes to you directly from... The Sofa of Brian Gaff... Blind user, so no pictures please Note this Signature is meaningless.! "harry" wrote in message ... On Friday, 1 February 2019 01:33:02 UTC, S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? It's c/s not cycles. (cycles per second) If you leave the time element out, it's meaningless. https://en.wikipedia.org/wiki/Hertz |
cycles to hertz - when?
On 01/02/2019 12:24, Jethro_uk wrote:
On Thu, 31 Jan 2019 20:32:57 -0500, S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? Not quite as specialist, but cropped up in chat a few days ago, is when did Centigrade become Celcius in the UK ? Because we sure as hell used centigrade at school. Never. Its Celsius and its IIRC not quite the same thing as Centigrade. 60s sometime. (also when did Peking change it's name ? And Bombay ? And when did "Islamic" become "Islamist" ? ) When political correctness canme in. 80s/90s. -- Climate Change: Socialism wearing a lab coat. |
cycles to hertz - when?
On 01/02/2019 12:24:36, Jethro_uk wrote:
On Thu, 31 Jan 2019 20:32:57 -0500, S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? Not quite as specialist, but cropped up in chat a few days ago, is when did Centigrade become Celcius in the UK ? Because we sure as hell used centigrade at school. Wikipedia says, "Centigrade, a historical forerunner to the Celsius temperature scale, synonymous in modern usage" (also when did Peking change it's name ? And Bombay ? And when did "Islamic" become "Islamist" ? ) Peking has always be Beijing, only through ignorance has it been called Peking. Same with Paris. Bombay? 1995 when the Indian government changed the name. There was a time when gay meant happy, change is a form of marching progress. Best live with it or get left behind. |
cycles to hertz - when?
Brian Gaff wrote:
One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. I often wonder why we have still got the two. Metres is of course very handy if you want to make your own aerial, but then you have this adjustment for the velocity factor for conductors. However I notice that when you get to really high frequencies they are termed milimetric wavelengths. By the time the wavelength nears that of light we use other terms to describe the frequency. Light frequencies, and especially infrared, are often still described as a wavelength in nanometres. Basically though the energy received at a point in a given time period has to be greater the higher the frequency. The wave particle duality still makes radiation of photons very interesting to me. One of the reasons I still tune the short wave bands even though in most cases I could get the same thing on the internet is that it means that a certain set of photons travels over a very random route from the transmitting aerial to mine. Oh and as somebody why has experienced an RF burn. touching a transmitting aerial is definitely not a good thing to do. Brian -- Roger Hayter |
cycles to hertz - when?
On 01/02/2019 09:23, Scott wrote:
On Fri, 01 Feb 2019 08:46:54 GMT, Harry Bloomfield wrote: Brian Gaff presented the following explanation : One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres = 299792.458/ kHz kHz = 299792.458/ metres I thought it was 300,000. The teaching at my school must have been a bit rubbish! There has been talk of redefining the metre so the speed of light in vacuo is precisely that. Since the metre isn't 1/10,000,000th the distance from the equator to the pole as intended, it shouldn't offend anybody. I suppose too much inertia has now made the change impossible. Another Dave -- Change nospam to techie |
cycles to hertz - when?
On 2/1/2019 7:34 AM, Fredxx wrote:
On 01/02/2019 12:24:36, Jethro_uk wrote: (also when did Peking change it's name ? And Bombay ? And when did "Islamic" become "Islamist" ? ) Peking has always be Beijing, only through ignorance has it been called Peking. Same with Paris. Sometimes it was Beiping or Peiping. |
cycles to hertz - when?
|
cycles to hertz - when?
On 01/02/2019 09:34, Andy Bennet wrote:
On 01/02/2019 09:32, Halmyre wrote: On Friday, February 1, 2019 at 8:15:19 AM UTC, Brian Gaff wrote: Not really. Â* It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. Â* I suppose its a good job that the scientist was not called humperdink. Or even this chap: https://en.wikipedia.org/wiki/August_Kundt Trump is a MKundt! Mkt presumably Bill |
cycles to hertz - when?
On 01/02/2019 08:46, Harry Bloomfield wrote:
Brian Gaff presented the following explanation : One thing that has always interested me is the fact that many shortwave stations even today, give the frequencies in Khz, but the band in metres. *Now I used to know the conversion by heart when I could see, but over the years its kind of faded, but I know it contains the speed of light in metres per second. metres =*** 299792.458/ kHz kHz =* 299792.458/ metres ...in a vacuum. I await with interest the essay on the conversion factor for BBC long wave from Droitwich :) Aren't the pips deliberately retarded so they are accurately received 100 miles away? Perfect for Lon^H^H^HSalford. -- Graham. %Profound_observation% |
cycles to hertz - when?
On 01/02/2019 10:30, Bob Eager wrote:
I know the Darwin family quite well because one of the University of Kent Colleges is named after Charles Darwin. That needs further explanation. I was talking to the oldest member of the family a few years ago, and he was saying that he actually felt an affinity with three of the Colleges - Darwin, Keynes and Eliot. I knew about the Darwin family being closely connected with, and intermarrying with, the Keynes family (which I also know, because of that). So I asked him why he felt an affinity with Rutherford. "Oh", said he. "Ernest was my godfather". I'm sure that ought to be on Quote Unquote or somewhere! Bill |
cycles to hertz - when?
In article ,
S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? They did. IIRC, the name changed in the '60s. -- *Why are they called apartments, when they're all stuck together? * Dave Plowman London SW To e-mail, change noise into sound. |
cycles to hertz - when?
"The Natural Philosopher" wrote in message
... On 01/02/2019 12:24, Jethro_uk wrote: On Thu, 31 Jan 2019 20:32:57 -0500, S Viemeister wrote: Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? Not quite as specialist, but cropped up in chat a few days ago, is when did Centigrade become Celcius in the UK ? Because we sure as hell used centigrade at school. Never. Its Celsius and its IIRC not quite the same thing as Centigrade. 60s sometime. I'm sure we were still referring to temperature in degrees centigrade, including in physics and chemistry at A level (ie not just colloquial usage) in the late 70s and early 80s. In contrast, I can't remember ever being taught about frequencies in cps rather than Hz, so that change happened (and was assimilated into teaching courses) earlier than that. Is there any difference in size or zero-point for deg centigrade and deg Celsius? I realise that the unit size of K is the same as deg C, but with a 0 origin at -273.15 deg C. I did Nuffield physics and chemistry courses at O and A level. I remember their insistence on expressing units with negative powers - so speeds in m.s^-1 rather than m/s, and densities in kg.m^-3 rather than kg/m^3 - which always struck me as pedantic and out of step with common usage. (where "^" denotes that what follows is superscript). I'm not sure how you were supposed to refer to such units in spoken words - did they want us to say "metres seconds to the minus one" or "metres per second" ;-) |
cycles to hertz - when?
"Fredxx" wrote in message
... (also when did Peking change it's name ? And Bombay ? And when did "Islamic" become "Islamist" ? ) Peking has always be Beijing, only through ignorance has it been called Peking. Same with Paris. Slightly different with names European cities. The pronunciation of Paris in English has always be Pariss rather than the proper French "Paree". Likewise for the French name for London, Londres. And our name Munich for what the Germans call München, and our spelling Hanover for the German city that they spell Hannover. It's only like England versus Angleterre, or Deutschland versus Germany versus Allemagne. |
cycles to hertz - when?
"Roger Hayter" wrote in message
... Light frequencies, and especially infrared, are often still described as a wavelength in nanometres. Whereas at one time they were quoted in Angstroms - when 1 Ȧ is 0.1 nm or 100 pm. |
cycles to hertz - when?
"bert" wrote in message
... The term cycles per second was largely replaced by hertz by the 1970s. One hobby magazine, Electronics Illustrated, declared their intention to stick with the traditional kc., Mc., etc. units.[8] They would! I think it was EI that also had a house style of putting dots between initials and always using lower-case except for metric prefixes, so kc.p.s.rather than kcps or kc/s (or kHz) Mc.p.s. rather than Mcps or Mc/s (or MHz) i.c. rather than IC (integrated circuit) p.c. rather than PC (personal computer) e.p.r.o.m. rather than EPROM which made it harder to read because the eye is attuned to trying to pronounce "words" of lower-case letters, whereas it is attuned to treating multiple capital letters as individual letters unless they can easily be pronounced. |
cycles to hertz - when?
"Bill Wright" wrote in message
... On 01/02/2019 09:34, Andy Bennet wrote: On 01/02/2019 09:32, Halmyre wrote: On Friday, February 1, 2019 at 8:15:19 AM UTC, Brian Gaff wrote: Not really. It was cycles when I was young. However to be honest it was probably done for the modern person who had never heard of cycles. I suppose its a good job that the scientist was not called humperdink. Or even this chap: https://en.wikipedia.org/wiki/August_Kundt Trump is a MKundt! Anyone who has read Anthony Horowitz's novel Magpie Murders will know what his character name Atticus Pund is an anagram of ;-) |
cycles to hertz - when?
On Thu, 31 Jan 2019 20:32:57 -0500, S Viemeister wrote:
Watching the Eddie Izzard film on the development of radar, I was surprised that they used 'megahertz' rather than 'megacycle'. Was this usage accurate for the period? The same film apparently has a plug being wired with brown/blue/gren-and- yellow flex. -- My posts are my copyright and if @diy_forums or Home Owners' Hub wish to copy them they can pay me £1 a message. Use the BIG mirror service in the UK: http://www.mirrorservice.org *lightning surge protection* - a w_tom conductor |
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