So, an unofficially-official answer I got was that the audio on both the shuttle and ISS sounds the same as it did in 1980 because the infrastructure is basically the same as it was in 1980.
Video has been upgraded several times because nasa cares very much about the ability to see everything as clearly as possible. Audio hasn't really been upgraded because all that matters is telephone bandwidth for clear communication.
The mic that is used on both the shuttle and ISS is a Crown GLM that has been ruggedized and mounted to a box with the PTT and preamp circuitry inside. Take the tone of that mic and compress the living daylights out of it, then compand it, then bandwidth limit it several times, and you get what you hear on the ground.
Video has been upgraded several times because nasa cares very much about the ability to see everything as clearly as possible. Audio hasn't really been upgraded because all that matters is telephone bandwidth for clear communication.
The mic that is used on both the shuttle and ISS is a Crown GLM that has been ruggedized and mounted to a box with the PTT and preamp circuitry inside. Take the tone of that mic and compress the living daylights out of it, then compand it, then bandwidth limit it several times, and you get what you hear on the ground.
besides, while technological improvements are likely easily within budget
mad, we might not necessarily want to hear everything going on up there in high resolution micro-detail (think of the gastro-intestinal ramifications of the diet) thank goodness the technology doesn't exist to transmit olfactory impressions
oh no, there's another escapee from the commode
But not as much junk nor total items so that seems to make the US the worst polluter no?
Yeah, true, though the difference is small anyway. One man's satellite is another man's debris
jd
Remember the rule, the wider the window the more dirt blows in. Keeping the bandwidth down to the bare minimum actually improves intelligibility in noisy environments. The audio is also processed to maximise intelligibility at the expense of what we would call "fidelity".
Amateur radio enthusiasts, especially those who participate in competitions, know the value of a good speech processor.
Amateur radio enthusiasts, especially those who participate in competitions, know the value of a good speech processor.
Yeah, true, though the difference is small anyway. One man's satellite is another man's debris
For such a serious guy you make me laugh a lot. Thanks for another one, Jan.
I think they should go back to CW and transmit via lingua Navajogensis:
http://navajocodetalkers.org/
http://navajocodetalkers.org/
Hello to everybody, it my first post at this forum.
It is about intelligibility, they ave to be understand. When the engines are on
the Donald duck sound is OK. The Donald duck sound is all about the mic they use. They chose the mic to be sure to be understand in any sound environment they are. If something append they don’t want to change the mic because the background ( fire, explosion ) is to loud . So they keep the Donald duck mic. Frankly a sure they don’t care as long as it is super efficient.
I met a Canadian astronaut and ask her what it sound like in the shuffling, "after i fink it what a weird question???". It sound like a computer room, lot of fan.
So we tack about the quality of communication. And that it it all about super efficiency, just like 386 it as no more bugs anymore.
The only place they take care about sound, is in the space station went do interview, duplex whit school, or recording science conference in the station. It a Shure SM-58, this mic is a tank, is sound good for the kind of job.
But if you thinking about it. When it sound Donald duck, it is sounding more real, more live. If it was sounding like a "voice over", it would seem to easy to comfortable.
I find what they do up there, and mostly in all the kind of "un-welcome" situation and constraint, it is most impressive.
So the donald duck mic sound like the ambiance, and i like it.
I have been working fore 20 years at sound for a big tv network, it is not the best mic that give you the best sound track.
Well it was my first post on this forum
Buy Buy everybody.
It is about intelligibility, they ave to be understand. When the engines are on
the Donald duck sound is OK. The Donald duck sound is all about the mic they use. They chose the mic to be sure to be understand in any sound environment they are. If something append they don’t want to change the mic because the background ( fire, explosion ) is to loud . So they keep the Donald duck mic. Frankly a sure they don’t care as long as it is super efficient.
I met a Canadian astronaut and ask her what it sound like in the shuffling, "after i fink it what a weird question???". It sound like a computer room, lot of fan.
So we tack about the quality of communication. And that it it all about super efficiency, just like 386 it as no more bugs anymore.
The only place they take care about sound, is in the space station went do interview, duplex whit school, or recording science conference in the station. It a Shure SM-58, this mic is a tank, is sound good for the kind of job.
But if you thinking about it. When it sound Donald duck, it is sounding more real, more live. If it was sounding like a "voice over", it would seem to easy to comfortable.
I find what they do up there, and mostly in all the kind of "un-welcome" situation and constraint, it is most impressive.
So the donald duck mic sound like the ambiance, and i like it.
I have been working fore 20 years at sound for a big tv network, it is not the best mic that give you the best sound track.
Well it was my first post on this forum
Buy Buy everybody.
It is true about the "telephone sound." Actually, the public affairs commentator has broadcast quality audio, but the spacecraft communications still adhere to the dictum of passing only a 300 to 3000 Hz voice frequency range and using a lot of clipping.
The one good advancement, from Apollo onward, is putting most of the audio on an FM subcarrier within a microwave signal. There's not much audio noise on the C or Ku links. There's actually a good plain-language description of how the Unified S Band Space Communications and Telemetry actually works, with a lot of NASA photos and documents.
Ever wonder what the "crackle noise" was when Challenger disintegrated? It was the analog FM voice subcarrier cutting out as the whole microvave signal vanished.
The Shuttle and ISS similarly have somewhat limited comms, so that they don't interfere with the command and telemetry subcarriers. I have always hoped that they would go to full high definition for public broadcasts and just leave the crew comms alone.
NASA is probably not going to spend money to go all-out with HD multimedia.
The one good advancement, from Apollo onward, is putting most of the audio on an FM subcarrier within a microwave signal. There's not much audio noise on the C or Ku links. There's actually a good plain-language description of how the Unified S Band Space Communications and Telemetry actually works, with a lot of NASA photos and documents.
Ever wonder what the "crackle noise" was when Challenger disintegrated? It was the analog FM voice subcarrier cutting out as the whole microvave signal vanished.
The Shuttle and ISS similarly have somewhat limited comms, so that they don't interfere with the command and telemetry subcarriers. I have always hoped that they would go to full high definition for public broadcasts and just leave the crew comms alone.
NASA is probably not going to spend money to go all-out with HD multimedia.
I don't know about 10 Gs. Our fighters can pull more than 10Gs or I should say they could if they weren't limited to 9. 9 will make most people black out. 9 Gs sustained for even a very short time that is. Israeli F-16s are not limited at any amount of Gs though. 5Gs will make you think you are going to die and if you are not in very good physical shape make you black out. You can handle a little more if you have a good G suit and also know how to do the hick properly then you could without them but when you get up to 10 Gs almost anybody will black out no matter what. The most dangerous thing about blacking out is not the time you are out but when you come to you go into convulsions. Not really good if you are flying at 600 knots close to the ground.
In WW2 the German JU-87 Stukas had auto pilots that would automatically pull the aircraft out of a dive and level it off until the pilot woke up. They would often black out from the Gs when they started pulling up after their dive.
As for Tanks I have no idea but I do know that our M1A2 tanks weigh something like 80,000 pounds or 80,000 tons I think (I will have to look that up because now I am confused but it is safe to say they are extremely heavy) so the kick from the gun is probably not that bad. Those are our main battle tanks and they have a 120mm main gun that is smoothbore believe it or not. They can shoot them accurately while going 50 miles per hour at as fast a rate as the loader can load the rounds.
There is an old Vietnam era tank called the Sheridan tank that is very light. It is made out of aluminum and the 82nd Airborne division (the only airborne division we have left the 101st is an Air Assault Division now and the 173rd is a brigade) still uses Sheridans. Those tanks have a 151mm gun and I know when they shoot it with a conventional round (they shoot rockets out of them too) it moves the tank a lot. They can't fire it 360 degrees because it will knock the tank over. Any anti-tank round will go through Sheridan like a hot knife through butter. I wouldn't expect they ever see 10 Gs either but if anybody does it would be them. They use them because they can take them up in aircraft and drop them out with a parachute without damaging them. You couldn't do either with an M1A2. One type of aircraft (C5B Galaxy) can carry a single one but it ruins the aircraft. Puts too much stress on the airframe.
I know a guy who was in the 82nd and drove a Sheridan tank. I will ask him if he knows.
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Modern vehicle intercom systems still use the telephone standard, speach intelligability being the main concern as stated, not fidelity. Plus you have to actively controll the back ground noise, especially in a tank, which can be very very loud, so the limited frequency band helps, also there is less data to transmit over a radio.
I made a mistake earlier - the audio downlink actually is all digital on S and Ku bands. There's the analog UHF too, but generally you hear the digital audio after a lot of processing. The crackle from Challenger was apparently transmitted on the downlink just before the breakup happened.
Found that info while searching for HD audio recordings of rocket sounds made around the launch site.
Found that info while searching for HD audio recordings of rocket sounds made around the launch site.
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