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  1. Subscriber FreakyKBH
    Acquired Taste...
    31 May '18 13:28
    What is the time delay for audio transmissions between earth and the moon?
  2. Subscriber sonhouse
    Fast and Curious
    31 May '18 16:22 / 4 edits
    Originally posted by @freakykbh
    What is the time delay for audio transmissions between earth and the moon?
    And double that for round trip actual conversation. Distance to Luna varies between 221,500 miles (or in civilized units, 356,393 Km) to 252,700 miles. 406,594 Km which means min of 1.189 seconds one way to 1.357 seconds one way.

    There is a tech you undoubtedly know nothing about: Amateur radio operators talking from moonbounce.

    They have massive (for hams anyway) antennae pointed at the moon and send a CQ out and it hits the moon and comes back to Earth, using the moon as a giant mirror, not an especially good one for sure but some of that signal comes back with enough strength to be heard by advanced amateur radio equipment, a signal loss of about 200+ DB but with 40 DB gain antenna's on both ends it is possible.

    So 1.273 average seconds goes to 2.5 odd seconds to have two way conversations and that happens all the time.

    What is your newest obvious agenda statement about that? Fake news, nobody can use the moon as a reflector?

    Astronomers use the retroreflector planted on the moon by US astronauts to gauge the distance to the moon within a centimeter BECAUSE of the retroreflector.

    Without the retroreflector on the surface, the laser signals would be WAY too weak AND spread out over low ground and mountains which would destroy the exact timing of the laser signals so the retroreflector gives an exact distance only to that mirror array and nothing else around it so they get a clean distance measure of Luna, showing it is receding from Earth at a rate of about a cm per year or thereabouts.

    So there are two sets of people using the moon as reflector.

    Your point is?
  3. Subscriber FreakyKBH
    Acquired Taste...
    31 May '18 17:24
    Originally posted by @sonhouse
    And double that for round trip actual conversation. Distance to Luna varies between 221,500 miles (or in civilized units, 356,393 Km) to 252,700 miles. 406,594 Km which means min of 1.189 seconds one way to 1.357 seconds one way.

    There is a tech you undoubtedly know nothing about: Amateur radio operators talking from moonbounce.

    They have massive ...[text shortened]... r thereabouts.

    So there are two sets of people using the moon as reflector.

    Your point is?
    You're a smart guy.
    Figure out the point for yourself.

    HINT: NASA ain't bound by your puny calculations or rules, even.
  4. Subscriber sonhouse
    Fast and Curious
    31 May '18 23:06
    Originally posted by @freakykbh
    You're a smart guy.
    Figure out the point for yourself.

    HINT: NASA ain't bound by your puny calculations or rules, even.
    Again, what drugs are you on now? What has NASA to do with moonbounce amateur radio? Do you deny we hams can do such a thing? I don't want to make this into 20 questions.

    If you have a point, point it out, otherwise go back to the kiddies forum.
  5. Subscriber FreakyKBH
    Acquired Taste...
    31 May '18 23:44
    Originally posted by @sonhouse
    Again, what drugs are you on now? What has NASA to do with moonbounce amateur radio? Do you deny we hams can do such a thing? I don't want to make this into 20 questions.

    If you have a point, point it out, otherwise go back to the kiddies forum.
    With a delay, is instaneous conversation at ALL possible--- anything wherein the relay could overlap or not require a minimum of, say, 1.23 seconds to deliver?
  6. Subscriber sonhouse
    Fast and Curious
    01 Jun '18 13:13
    Originally posted by @freakykbh
    With a delay, is instaneous conversation at ALL possible--- anything wherein the relay could overlap or not require a minimum of, say, 1.23 seconds to deliver?
    The whole idea of instantaneous transmission of information seems so far forbidden.
    Unless there is a way we could work out quantum superposition which SEEMS to be instantaneous but the universe may work in such a way as even if it is instant, we can't use it for transmission of data instantly.

    We are so far stuck with the speed of light and that sucks for projects like remote control of extra terrestrial vehicles.

    Even on the moon if we have a drone like device (no air so it won't fly without rockets) but with a 2 and 1/2 second delay, that severely limits the speed at which a little remote control car on the moon can travel. As it drives across the moon, it could encounter a cliff or some such. With a 2 second delay it could drive right over it before the operator on Earth could correct the trajectory of the drive.

    So it would have to go slow.

    Now think about a remote vehicle on Mars where the delay is several minutes.

    It would be near impossible to control such a vehicle from Earth at all.

    THEREFORE what we really do is to have onboard AI that recognizes barriers and such and is able to steer around such obstacles.

    That is how the big boys do it. Local intelligence built in computer control, which is how we get probes to work a billion miles from Earth where the delay there is more like 2 HOURS per round trip data cycle.

    You may choose to poo poo all of that but that is how it is in reality.
  7. Subscriber FreakyKBH
    Acquired Taste...
    01 Jun '18 14:30
    Originally posted by @sonhouse
    The whole idea of instantaneous transmission of information seems so far forbidden.
    Unless there is a way we could work out quantum superposition which SEEMS to be instantaneous but the universe may work in such a way as even if it is instant, we can't use it for transmission of data instantly.

    We are so far stuck with the speed of light and that sucks ...[text shortened]... ound trip data cycle.

    You may choose to poo poo all of that but that is how it is in reality.
    So what you're saying is...
    It isn't possible to have LESS THAN 1.23 seconds of delay between audio transmissions.


    Is this true?
  8. Subscriber sonhouse
    Fast and Curious
    01 Jun '18 15:39
    Originally posted by @freakykbh
    So what you're saying is...
    It isn't possible to have LESS THAN 1.23 seconds of delay between audio transmissions.


    Is this true?
    You can't think through even that detail? OF COURSE it is POSSIBLE to have less than a second delay. I requires the transmitter and receiver to be closer than Luna.

    For instance, the ISS is a couple hundred miles up but the horizontal distance to a dish might be more like 2000 miles and in that case the round trip is 4000 miles and that is roughly 50 millisecond delay.

    The round trip delay is simple, about 12 microseconds per mile, light goes about 6 microseconds per mile so double that for transmit and receives so do the math, 1000 miles, 12 MILLIseconds round trip.
    100,000 miles would be about one second, 50K miles each way. 1 million miles, about 10 second delay.

    That is why they use autonomous computers able to understand terrain and travel between planets, corrections and such.

    They can track spacecraft very precisely and humans can make mid course corrections they predict will put the craft in the exact right window to do whatever orbit around whatever planet they are aiming at.

    That is because they have days or weeks to make the calculations as to just how much thrust and vector of such thrust for just how long to make the corrections.

    That all works because even if the delay time is an hour (light travels roughly one billion miles per hour) they can do that kind of thing in advance.

    Driving around on a planet HAS to be done by AI onboard because that is done in real time, they say drive at 10 mph which is about 15 feet per second, you can see some kind of delay of 10 minutes or so, best case for Mars, it would be impossible to see an obstacle in time and it would soon crash into something or go over a cliff.

    So remote control is totally out for such vehicles.
  9. Subscriber FreakyKBH
    Acquired Taste...
    01 Jun '18 17:05
    Originally posted by @sonhouse
    You can't think through even that detail? OF COURSE it is POSSIBLE to have less than a second delay. I requires the transmitter and receiver to be closer than Luna.

    For instance, the ISS is a couple hundred miles up but the horizontal distance to a dish might be more like 2000 miles and in that case the round trip is 4000 miles and that is roughly 50 m ...[text shortened]... crash into something or go over a cliff.

    So remote control is totally out for such vehicles.
    Let me ask it another way.

    You're standing on the moon.
    I'm standing on my front porch, sipping a lemonade (made from freshly squeezed Meyer lemons which had been stored in a climate-controlled air-inducted cooling container--- laypeople such as yourself call it a refrigerator--- within 16 hours of harvest to ensure maximum optimal sugar-to-tart ratio) in a glass which also contained three and one half cubes of ice (made from triple distilled spring water) in my left hand.
    In my right hand, I hold the mic with which to control conversational flow between you and me.
    You say something witty and wise, such as, say, "Hey, FreakyKBH! I'm on the motherplucking moon, yo! What are you doing, loser?"
    Once you complete those 17 syllables, how long before I hear them?
    As in, what is the smallest amount of time between you saying and me hearing?
  10. Subscriber sonhouse
    Fast and Curious
    01 Jun '18 18:25
    Originally posted by @freakykbh
    Let me ask it another way.

    You're standing on the moon.
    I'm standing on my front porch, sipping a lemonade (made from freshly squeezed Meyer lemons which had been stored in a climate-controlled air-inducted cooling container--- laypeople such as yourself call it a refrigerator--- within 16 hours of harvest to ensure maximum optimal sugar-to-tart ratio ...[text shortened]... fore I hear them?
    As in, what is the smallest amount of time between you saying and me hearing?
    What part of a round trip time do you not understand? lets say it is 240,000 miles to the moon and lets call it a 1 and 1/4 second time to get the signal to the moon and then you reply in one second. So 1.25 plus 1 plus 1.25 seconds =3.5 seconds. What don't you understand about that? If I reply in one half second, the round trip is 3 seconds.

    Is there something esoteric about that? Did you not understand my statement that light and RF takes 6 microseconds to go one mile? Is that too hard to understand? So with radar, a target one mile away, radar pulse goes out, 6 microseconds later it hits the target, the return takes another 6 microseconds. So 12 microseconds goes by between emission of pulse and return.

    This is not rocket science.
  11. Subscriber FreakyKBH
    Acquired Taste...
    02 Jun '18 18:42
    Originally posted by @sonhouse
    What part of a round trip time do you not understand? lets say it is 240,000 miles to the moon and lets call it a 1 and 1/4 second time to get the signal to the moon and then you reply in one second. So 1.25 plus 1 plus 1.25 seconds =3.5 seconds. What don't you understand about that? If I reply in one half second, the round trip is 3 seconds.

    Is there s ...[text shortened]... o 12 microseconds goes by between emission of pulse and return.

    This is not rocket science.
    Rocket science.
    Riiiight.
    It ain't rocket science.

    If it takes the originally stated 1.23 seconds at a minimum, it simply isn't possible for the transmission to be heard until that 1.23 seconds has passed.
    We couldn't have immediate conversation, but rather, delayed.
    Delayed by 1.23 seconds between each burst of response.

    So if you were to hear conversation which lacked that 1.23 seconds of delay, you would know the people conversing could not be the stated distance apart.

    Do I have it right?
  12. Subscriber sonhouse
    Fast and Curious
    02 Jun '18 19:14 / 2 edits
    Originally posted by @freakykbh
    Rocket science.
    Riiiight.
    It ain't rocket science.

    If it takes the originally stated 1.23 seconds at a minimum, it simply isn't possible for the transmission to be heard until that 1.23 seconds has passed.
    We couldn't have immediate conversation, but rather, delayed.
    Delayed by 1.23 seconds between each burst of response.

    So if you were to hear ...[text shortened]... would know the people conversing could not be the stated distance apart.

    Do I have it right?
    Yes, did you not see my post showing the speed of light is about 6 microseconds per mile?
    So one mile apart, you won't know about it for 6 microseconds after transmission starts and the return takes 12 microseconds.
    So the bit with the 1.25 odd seconds light needs to traverse the distance from Earth to Luna would be the minimum time you could know a signal has been sent.

    Like if somehow the sun was teleported a thousand light years away in an instant, we would not know anything about that for 8 minutes and the gravitational field the sun generates (the bending of space around the sun) would not start to effect the trajectory of Earth for 8 minutes either.

    Earth would be taking its curved path around the sun for 8 minutes but then it would go off in a straight line with whatever curve of space-time is left over from the stars near us and the total curve of the galaxy and the like.

    Are you seriously interested in the subject or are you leading up to more theories about your agenda having to do with the flat Earth stuff?

    I am trying not to inject pejoratives here.
  13. Subscriber FreakyKBH
    Acquired Taste...
    02 Jun '18 23:20
    Originally posted by @sonhouse
    Yes, did you not see my post showing the speed of light is about 6 microseconds per mile?
    So one mile apart, you won't know about it for 6 microseconds after transmission starts and the return takes 12 microseconds.
    So the bit with the 1.25 odd seconds light needs to traverse the distance from Earth to Luna would be the minimum time you could know a sign ...[text shortened]... r agenda having to do with the flat Earth stuff?

    I am trying not to inject pejoratives here.
    Interested?
    You're kidding, right?
    I'm the one who brought it up.
    I'm going to characterize you as agreeing with the following claim, so correct it if it's wrong in any way, shape or form.
    It is not necessary for you to add anything, to elaborate quantum physics, black holes or any other incidental information.
    A simple yes or no is all that is required.

    If your transmission to me takes less than 1.23 seconds, you cannot be on the moon.
    Yes or no?
  14. Subscriber sonhouse
    Fast and Curious
    03 Jun '18 14:10
    Originally posted by @freakykbh
    Interested?
    You're kidding, right?
    I'm the one who brought it up.
    I'm going to characterize you as agreeing with the following claim, so correct it if it's wrong in any way, shape or form.
    It is not necessary for you to add anything, to elaborate quantum physics, black holes or any other incidental information.
    A simple yes or no is all that is requi ...[text shortened]...
    If your transmission to me takes less than 1.23 seconds, you cannot be on the moon.
    Yes or no?
    Ah, now I see your agenda. The answer to your question is yes, we cannot be on the moon if the time delay is less than 1.2 seconds. Actually less than 2.5 seconds.
    So now your other shoe drops, conclusive proof the moon landing communications were instantaneous therefore the moon landings were fake.

    How am I doing so far?
  15. Subscriber FreakyKBH
    Acquired Taste...
    03 Jun '18 15:27
    Originally posted by @sonhouse
    Ah, now I see your agenda. The answer to your question is yes, we cannot be on the moon if the time delay is less than 1.2 seconds. Actually less than 2.5 seconds.
    So now your other shoe drops, conclusive proof the moon landing communications were instantaneous therefore the moon landings were fake.

    How am I doing so far?
    Damn!
    You're good!
    Any transmission which took less than 1.23 seconds to hear proves the distance could not be over 230,000 miles away.

    Oops.
    They done effed up, huh.
    We only need ONE such transmission to claim something is amiss, but there are hundreds of such exchanges.

    Explain that one, um, those anomalies, expert.