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Things that make you :)


Andy Y
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One thing I am aware of (and it is very annoying) is when my colleague and I are on a conference call to the USA using separate phones, there is a couple of seconds delay between him speaking and me hearing what he is saying on the call!

 

Jim

 

 

Given the size of the continent, the properties and thus their actual real estate, I wouldn't be too sure about that ;)

 

Mind, even if electricity, light and radio waves have a very high speed, there's still a propagation time involved. Admittedly it'd be in the microsecond range, but it's still there! It's also worth noting that the most common way for signals to travel from the UK to Aus is not via the Earth surface, but via satellites in space, increasing the distance the signal travels considerably! And each satellite introduces its own delay in the signal. Again, very small, but still notable.

 

The delay of a couple of seconds indicates that the call has been routed via satellites, with the attendant propagation delay.

 

Back in the days of analogue satellite TV, I was involved in specifying (and eventually installing & commissioning) a piece of satellite ranging equipment to determine how far the spacecraft were from the ground station. The equipment measured the time between transmitting a TV frame sync pulse and receiving the pulse (such pulse was easy to pull out of the TV signal with TV decoder ICs). If the satellite ranging distance was measured as being in the next village, or out by the moon, then we had hold of the wrong returning sync pulse!

 

I would presume that in these days of digital TV, the measurement would be make on a particular digital pattern.

 

This week I was involved in a videoconference with an office in Hong Kong, and there was no appreciable delay between speaking and then hearing a response. Clearly, the company involved had paid for the transmissions to be routed via fibre optics rather than satellites (well I was impressed). Note - signal speed in fibre optics is still slower than by radio waves over a given direct distance.

 

The analogue radio receivers demodulate the audio and send it out the speaker(s) virtually instantaneously, whereas the digital radios need a block of data to demodulate. This block is then sent out the speaker(s) while the next block is arriving and decoding. Hence the large time difference between the analogue audio and the digital audio. Different digital radios (and TVs) perform this block decoding part at different speeds to each other, thus giving the similar echo effect between digital receivers in the same house.

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I recall being told, that if you listen to a radio in Australia, you actually get to hear it, before someone standing on the other side of the Thames does. Assuming a live broadcast, of course. Such is the difference between the speed of sound & that of light.

Ahhh yes but .................. this was all explained when I was a kid    :mosking:

https://en.wikipedia.org/wiki/Big_Ben_Strikes_Again

Edited by Southernman46
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Registration  on the first day back at school in London....

Ahmed  Al Sheriah ...................................."here"

Mustafa  Al Sheriah ..................................."here"

Fatima  El Bindiri ......................................"here"

Ali  Acmah Shabeeb ................................."here"

Ali  Sun Al En ..........................No answer

Ali Sun  Al En?

Little  girl at the back stands up and yells ........ "It's pronounced Alison Allen, for f**k  sake !"

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At least they should have parked it properly, it's now blocking the junction in defiance of the highway code that stipulates a 50ft stretch should be left open for pedestrians to cross the road and have sufficient view of said road for a safe crossing.

 

;)

 

I suppose you could always put a clamp on its propeller....

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My mother has wings today. It's making it difficult to sit in any chair because she cannot fold them. Since I am not privileged to see them, I cannot provide any useful advice. Although I did suggest that instead of sitting she could perhaps hover using her wings? That got me a very old fashioned look, and the information that I was being cheeky, it should be obvious that they are not for flying with. But she has dozed off now, so I can use the 'bloody machine' (pointed finger) to entertain myself a little.

 

That's today's Alzheimer report. She's as happy as Larry because the biscuits of the day are custard creams and bourbons which are her runaway favourites. You just have to laugh at the random nonsense notions, because the alternative is no good at all.

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My mother has wings today. It's making it difficult to sit in any chair because she cannot fold them. Since I am not privileged to see them, I cannot provide any useful advice. Although I did suggest that instead of sitting she could perhaps hover using her wings? That got me a very old fashioned look, and the information that I was being cheeky, it should be obvious that they are not for flying with. But she has dozed off now, so I can use the 'bloody machine' (pointed finger) to entertain myself a little.

 

That's today's Alzheimer report. She's as happy as Larry because the biscuits of the day are custard creams and bourbons which are her runaway favourites. You just have to laugh at the random nonsense notions, because the alternative is no good at all.

 

thats lovely, genuinely bought a tear of joy to my eye

 

nothing else to add

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