Black box flight recorder - location signal?

Where was your ADS-B receiver when they needed it?

Maximum range at 37.5 KHz is 4-5 Km and maybe 6-7 Km under good conditions. The 10 Km range seems a stretch and is only for the 10 KHz version. Note that ASCA towed device is only rated to 0.3 km water depth: On April 8, it will be 30 days, when the transponder in the flight recorder allegedly dies. I've read somewhere that it might be programmed to reduce power output instead of turning off. I'm not certain of the logic here, but my guess(tm) is that it's to reduce clutter in case they need to search for multiple devices in the same time frame. I don't know if it ever turns off completely. If so, it's also possible that this finding might be a long lost drug shipment or research device.

Ummm... fish finders are SONAR transponders, not hyrophones listening for a 37.5 KHz burst once every second. You won't find any fish with just a microphone.

Must be a conspiracy:

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

There's a possible example of a coding technique at: I have no idea if the device on MH370 has this capability. Probably easier to just send Morse Code.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

It's this:

A simple ruggedized acoustic transducer:

On a sunny day (Sun, 06 Apr 2014 09:20:16 -0700) it happened Jeff Liebermann wrote in :

Makes me wonder why they do not use a transponder in the planes. Very low power consumption listening for a ping (maybe a special code), and than reply with a very strong pulse. Average power good for > a year I'd think. Can I get a patent now??

Yea, well, I have opped the idea the thing is actually in orbit. Nobody objected...

Whom? The fish? I don't think hanging a transponder on a fish in order to find other fish is going to be useful.

If you mean crash locators, the device would be more complexicated by the addition of a hydrophone, amplifiers, decoder(?), and transponding hardware. In my never humble opinion, commercial jets should also carry an external ELT crash locator, similar to the overpriced units required on smaller aircraft. However, instead of having it detach and deploy on impact, add a pressure release switch to activate when the aircraft crashes in the water. Such a device won't locate the crash site exactly, but will be useful in dramatically reducing the search area.

I like how the Dukane device offer a device that will operate to

10,000 Km depth, but can't easily be found at that depth.

The problem with listening at low audio frequencies is that the ocean is a rather noisy place. This graph doesn't cover 37.5 KHz, but I think you'll get the idea:

Hint: Over 1 year lifetime is bad for business. Make it blow up more often and you'll sell more.

Sure. Just send me some cash and print you a patent document suitable for framing. However, you'll have to wait as these came first:

I'm inclined to believe that MH370 never left the airport. That's the only place they haven't searched. Probably stolen and scrapped for titanium by thieves formerly in the copper salvage business. You read it here first.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

I've flown in and out of the "new" Kuala Lumpur airport a few times.. it's modern and not a small airport. The plane was tracked by ATC well out..

Also, there's probably only a few hundred thousand dollars worth of Ti in a 777. Hardly worth an elaborate scheme. Sharks with lasers?

Best regards, Spehro Pefhany

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"it's the network..."                          "The Journey is the reward" 
speff@interlog.com             Info for manufacturers: http://www.trexon.com 
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

The bigger airports have more places to hide an aircraft especially disassembled. With all the aircraft coming and going, an extra aircraft probably won't be noticed.

Spoofed perhaps? One can't trust anything that isn't encrypted these days.

Carbon fiber scrap sell for $35/lb while titanium scrap is only $6/lb: Ummm... are there any eagles in Malaysia in need of nesting material? The avionics are certainly sellable. No Boeing 777 seats available on eBay, which is a problem. However, there seems to be a shortage of

777 parts, which means there's a market: "Scarce 777 Parts Will Affect Aftermarket" It seems a better idea to steal the aircraft in the airport, than in the middle of the ocean: "If I was going to steal the aeroplane, that would be the point I would do it," Stephen Buzdygan, a former British Airways pilot who flew Boeing 777s, told The Telegraph." Therefore, I believe my theory of the aircraft being stolen by scrap dealers and parts jobbers is about as credible as some of the other available theories.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

That's a pretty low bar, so I'll have to agree.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward" 
speff@interlog.com             Info for manufacturers: http://www.trexon.com 
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Id go with the "death plane" theory that the plane caught fire, asphyxiated the people, and cruised to its grave. There evidently were flammable lithium batteries on board.

I flew Malaysian air (MA) to India a few years ago, and MA was widely considered to be an airline of last resort - poorly run. They lost my luggage, so I had to wear Indian clothes. That's a dhoti which is just a piece of cloth worn around you.

I visited their offices in Kuala Lumpur, and the official took me down to a huge room in the basement. "See," he said, "we lose the luggage of thousands of passengers every month." There were thousands of items. He seemed proud of it.

j

Once you combine the carbon fiber with the resin, it probably isn't worth very much. The raw material of course has value. Even prepreg if it isn't too old.

Given the barrier to entry for mode-s/ADS-B receivers is $8 and PC, there should be lots of receivers out there. But if you turn off the transponder, there is no ADS-B or mode-s to receive.

Making the black box be a transponder is an interesting idea, but you need to meditate on your navel first. You need two events to work to get a result. The box has to hear you and you have to hear the box. I think it is far better just to let the box ping.

I worked on sonobouys in the dark ages. The frequency response of the filter in the old analog sonobouys had a 6dB/oct rise. I figured they were equalizing the sea transmission loss, as in a matched filter. But looking at the table, maybe they were just trying to crate a flat noise floor. It wasn't my job to ask why, since that isn't how the military works. You get a spec and make the part.

I have to say the Malaysian government has been totally inept. Look how long it took just to get the correct transcript of the ATC conversation. I was open minded about this at the start, but it has become clear as time progressed that the Malaysian government is clueless.

I doubt there is much secrecy in ping detection gear. They probably have a towed array to get it out of the way of the noise of the ship. Pretty common in submarine detection from ships. There could possibly be sonobouys for ping detection.

On a sunny day (Sun, 06 Apr 2014 14:23:15 -0700) it happened Jeff Liebermann wrote in :

AFAIK NAVY has some very powerful sonar, if I have to belive teh greenpices sort of people it is powerful enough to destroy wales ears and strand them hundreds of miles aways opr something. The fact is that a ship wit hte righ tequipment can generate a VERY powerfull ping, this moves the power problem to the transmitter, you only need a moderate sensiotive (say cheap) receover in te htransponder. The super sensitive receiver can be on the ship. transponde rshould propbably usue some delay for any echos to be gone befre replying to teh ping.. Logic.

ee that wheel thing could be useful...

But where are the people?

On a sunny day (Sun, 06 Apr 2014 20:44:49 -0700) it happened miso wrote in :

No, as then you have the power problem. and- a transponder that only pings when requested can even transmit at a much higher power and be heard further away. Its simple. Its basics. Transponder thing is done in many places. Even in g*m cheap key finders, where you whistle and it whistles back.

These ARE the dark ages. Check you NAVel

But there could be, and in this case the ping request should be encrypted. Just so the 5$23 cent ebay ping activator does not empty all batteries at the airport. ;-)

Its submnarine detection stuff, AFAIK there are receivers all over the globe at the sea bottom sending signals, but hey that is classified so maybe we need an other whatshis name snow-man?

Last I remember was a large array of ultrasonic microphones like an underwater lens or telescope, something that was classified, but could detect cannot remember what, but was discussed here ten years ago or so. Do Not Underestimate The Stuff US Army And Navy Have. Was neural net actually.

Ideally you would have both pinger and transponder. But you have to consider this has been thought out over the years and the pinger won the argument.

You failed to meditate on your navel. The pinger is more reliable since it doesn't have to respond to any stimulus. Encryption? You really need to keep things simple. The goal is to have the system work. As you cascade events in a trigger, you multiply the probabilities of success for each event, and the product only moves in one direction: down. MH370 is a very unusual accident since most aircraft have flight following. A pinger is fine.

Towed array beamformers are old hat. There are probably some classified elements to modern implementations, but the technology is really old school. The signal processing was done with freakin' bucket brigade chips in the darker ages (70s).

This paper indicates beamforming sonar dates back to WWII. I have no idea what they used then for delay elements.

On a sunny day (Mon, 07 Apr 2014 10:42:13 -0700) it happened miso wrote in :

Yea, but this is 2014 (although apparently not for some).

You know, miso, I have heard that stupid(tm) argument in the same way about transmitters. Amateurs were required to learn morse.. for the short wave bands...

It was 'thought' that some idiot would be pushing 2 wires together on a sparkplug or something in an emergency situation and then you could decode dah dah dah di di di day da dooo or whatever it was.

Modern equipment is so much more complicated on the electronics level that all that is nonsense.

Complexity does _not_ reduce reliability, used the right way extra stuff _increases_ reliability. We have zillions of transistors in processors, very complex signal processing algos, extremely complex modulation system, and now all of the sudden for you a key finder is too complicated? is there a HOLE where your navel should be?

This was about neural net interpretation of the data.

Liebermann

:

something.

Some 4 decades ago when i was in Uncle Sugar's Kanoe Klub i was on a destroyer. The sonar on that ship was capable of outputting a Megawatt. No, i don't know how they coupled it to the water and avoided cavitation.

powerfull ping,

htransponder.

befre replying to teh ping..

We are not talking about a chip or a self contained unit. If you ever studied communications in college, you have three elements: transmitter, channel and receiver.

You are free to insult me, stop your feet or whatever, but the channel is the channel is the channel and there is nothing you can do about it. Well other than do your matched filter. Loss and noise are real life.

It is undeniable that the probably of each stage needs to be multiplied. This is science. Again, insult me and stomp your feet, there is no way around this.

Modern equipment is complicated because you can reliably put millions of working transistors on a chip. But the science hasn't changed. Rather every element is very reliable. But if you look at the history of silicon based integrated circuits, at least of the MOSFET flavor, the chip sizes haven't grown all that much over the years. Rather the devices get smaller. This is due to wafer defect density not really scaling over the years.

Many datasheets have a transistor count on them. The rel people use the die size and number of transistors to make a yield estimate. Why the customer needs to know is beyond me. I never had much faith in such a scheme because all transistors are not equal in importance, But the component count is part of the procedure, and it is easier to shut up and give the powers that be the number rather than ask why you do such nonsense.

Regarding complicated digital system, I have one word: boot! It is damn hard to make a reliably computer, hence redundancy and a voting scheme is used in mission critical situations. Now what you can do is what the Navy does in submarine hunting, namely drop lots of sensors and then correlate them with some big ass computer on the P-3 or P-8.

The sonobouy is one of the cheapest pieces of military gear made, and for a good reason. They toss a bunch of them, and some are allowed not to work. The devices are built to commercial standards. One nice thing about the ocean is the temperature range isn't all that extreme. That is one reason the devices can be cheap. This is similar to the radiosonde, where you kind of expect never to see it again. In the case of the sonobouys, they sink them.

On a sunny day (Mon, 07 Apr 2014 22:48:32 -0700) it happened miso wrote in :

You know miso, I kill filed you in the past because you were incapable of correct quoting. I understand you worked for or at Maxim, and the Maxim chips I got (from ebay) were garbage, went into latchup. Either way, maybe those were counterfeit, or Maxim does not go after counterfeits, both bad, or you designed them, also bad, I have designed Maxim out. You wont see their chips anymore in my designs. The way you preach from your tower and the fact you have no real experience or anything to show here for real design, neither discrete nor with chips, is sign enough you are basically clueless and just parroting some stuff. Just a quick google search without even understanding the issue here.

It is true is that you can make systems better by adding complexity. These day, as opposed to the Morse spark transmitter of your mind set, in an emergency, people use their cellphones, (a very very complicated advanced technology and infrastructure) an call the local alarm number and say: Help!! the operator will then probably ask: "Whats up?", and they will cry: 'MISO is here'. help will immediately be dispatched in the form of well white coats etc you (guessed it). So complexity is already, in 2014, part of dally life. Air industry always is a bit behind, the old DC9 or whatever is still flying, and they cannot get the F35 soft - and hardware working, while the world already has 3D teevee and drones go for a few hundred dollars, encrypted with Wifi at that, so things need to be upped technologically logically in that area. When you left brainwash in the early last century things probably were different, but again, today keyfinders go for a few dollars, let me find one for you:

1811 results as of this moment.

You know you are the one insulting, I am merely measuring your level. Bye

On a sunny day (Mon, 07 Apr 2014 22:48:32 -0700) it happened miso wrote in :

You know miso, I kill filed you in the past because you were incapable of correct quoting. I understand you worked for or at Maxim, and the Maxim chips I got (from ebay) were garbage, went into latchup. Either way, maybe those were counterfeit, or Maxim does not go after counterfeits, both bad, or you designed them, also bad, I have designed Maxim out. You wont see their chips anymore in my designs. The way you preach from your tower and the fact you have no real experience or anything to show here for real design, neither discrete nor with chips, is sign enough you are basically clueless and just parroting some stuff. Just a quick google search without even understanding the issue here.

It is true is that you can make systems better by adding complexity. These day, as opposed to the Morse spark transmitter of your mind set, in an emergency, people use their cellphones, (a very very complicated advanced technology and infrastructure) an call the local alarm number and say: Help!! the operator will then probably ask: "Whats up?", and they will cry: 'MISO is here'. help will immediately be dispatched in the form of well white coats etc you (guessed it). So complexity is already, in 2014, part of dally life. Air industry always is a bit behind, the old DC9 or whatever is still flying, and they cannot get the F35 soft - and hardware working, while the world already has 3D teevee and drones go for a few hundred dollars, encrypted with Wifi at that, so things need to be upped technologically logically in that area. When you left brainwash in the early last century things probably were different, but again, today keyfinders go for a few dollars, let me find one for you:

1811 results as of this moment.

You know you are the one insulting, I am merely measuring your level. Bye

No price. No "Buy it now" button.

How do they expect to sell any?

Sylvia.