Wikipedia:Reference desk/Archives/Science/2014 December 16

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December 16

Why we shouldn't eat already dead animal instead of killing & eat them?

Question by Ram nareshji (talk) 02:53, 16 December 2014 (UTC) deleted as possible copyvio [1] given the lack of any reassurance from the editor that they are the original author. Nil Einne (talk) 13:29, 18 December 2014 (UTC)

One reason dead animals are not eaten is they may have died from a disease that could be transmitted to the person who eats meat from the carcass. Another reason is that since animals die of natural causes at unpredictable times, it would be difficult to butcher the carcass quickly enough to prevent decomposition.

But the biggest reason animals are killed rather than allowed to die of natural causes is that cattle are slaughtered before three years of age. If they were allowed to die of natural causes, they would have to be fed for several years, which would greatly increase the cost of beef. Jc3s5h (talk) 04:15, 16 December 2014 (UTC)

If found soon after death, it may become roadkill cuisine. Rmhermen (talk) 04:35, 16 December 2014 (UTC)

Mutton sometimes comes from sheep kept for wool production, which died of old age. StuRat (talk) 05:44, 16 December 2014 (UTC)

Have you got a source for that StuRat? Dying of old age implies no slaughter just waiting. Hmm, horrible. Richard Avery (talk) 07:52, 16 December 2014 (UTC)

This would be more common with subsistence farmers. Dairy animals would be another example. Basically they are kept alive for their primary use as long as possible, then used for meat after they die. StuRat (talk) 16:57, 16 December 2014 (UTC)

If you find a dead animal, it may also contain parasites. Some are obvious, like maggots, others may not be, like trichinosis, and may be potentially contagious. StuRat (talk) 05:48, 16 December 2014 (UTC)

As ever I wonder which planet you are from. The animal,before it was dead, also had the parasites. Including, quite possibly, maggots, which while they may not whet your appetite are edible. Greglocock (talk) 10:38, 16 December 2014 (UTC)

"Finding them dead" implies they weren't raised on a farm under controlled conditions, so are presumably more likely to have parasites. Maggots, however, normally are only found on dead tissue, although it is possible for the dead tissue to be on a live animal. But, after death the number of parasites quickly increases (although perhaps I should have called them "insect and microscopic scavengers", not parasites, in a dead animal). Also, existing parasites can rapidly increase in number, after death, due to the lack of immune of other responses from the host(s) (like chimps picking bugs off each other). StuRat (talk) 16:57, 16 December 2014 (UTC)

Tradition - religious tradition primarily - compels many people to make sure to not eat dead (deceased), improperly killed, severely sick or congenitally deficient animal. In Judaism, these fall under nevelah and treifah categories, see terefah. The original purpose of these commandments and rules may have been to ensure cleanness, both physical (hygiene) and spiritual (morality). Dr Dima (talk) 18:34, 16 December 2014 (UTC)

• If I might sum up the above. The OP's fatherly advice was indeed a good dictum. And with all dictums there are exceptions. If a person is knowledgeable about how to judge the carcass as low risk and knows how to prepare and cook it safely. Then it could be eaten without suffering ill health. Outside that exception – then its better not to. Otherwise one could very well become ill or even end up as a cold stiff carcass oneself.--Aspro (talk) 02:52, 17 December 2014 (UTC)

Why does anxiety cause diarrhea or constipation?

Question deleted as probable copyvio by Ram nareshji as remarked below Nil Einne (talk) 15:06, 16 December 2014 (UTC)

Why are you copy-pasting questions from other websites into our reference desks? [2] AndyTheGrump (talk) 05:37, 16 December 2014 (UTC)

Heh, maybe someone is doing a sociological experiment to see whether our desk is better than theirs, or vice versa, by asking the same question both places and/or copy-pasting. If so, then let us oblige by answering the question, while also fouling up the experiment by knowing it is active, as it is a positive good to foil the schemes of those who hope to learn to predict us. But... if you go on PubMed and type anxiety and constipation, anxiety and diarrhea, you're in for a slog. At a quick look there's a lot of data about irritable bowel syndrome, where there's a definite comorbidity; the neuroendocrinology of the bowel itself is at issue: [3] But of course we all know the jocular phrases about needing a change of underwear after a scary situation, so it has to be a more general relationship. But I can't really dive into this right now... Wnt (talk) 06:20, 16 December 2014 (UTC)

The answer is in the parasympathetic nervous system. Vespine (talk) 22:18, 16 December 2014 (UTC)

Because anxiety causes the release of adrenaline, which speeds up the bodily processes, including the rate at which food is passed through the body [4][5]. I have often wondered whether diarrhea is just an unwanted side effect of the adrenaline rush, or whether it is a deliberate ploy by the body to evacuate the bowels quickly so you have less weight to carry and can run more quickly. However, I don't suppose there is any way to prove that one way or the other. If it is the latter then wearing underpants tends to defeat the object of that response. Richerman (talk) 09:19, 17 December 2014 (UTC)

• For the record, irritable bowl syndrome (linked above) has three types, one with chronic diarrhea, one with constipation, and one that fluctuates between between periods of diarrhea and constipation. Typically, episodes occur over days or weeks, and alternate with periods of relief. There's no evidence adrenaline is the mediator of IBS, and treatment usually consists of ameliorating the symptoms with stool softener or anti-diarrheals, as the cause is unknown. (There is indeed co-morbidity with anxiety, which can be treated by benzodiazepines and other means.) Evacuation due to the fight-or-flight response is a one-time thing on a far smaller timescale, and does not involve constipation. μηδείς (talk) 22:12, 17 December 2014 (UTC)

Anxiety, which is a known factor in IBS, causes adrenaline to be released on a regular basis due to a perceived stressor - see: here. Richerman (talk) 10:55, 18 December 2014 (UTC)

Sound from laying your head on your hand

First off, I'm not looking for a medical diagnosis or advice. I don't think this is a problem and I think it's probably something everyone can experience.

When I lay on my side and put my head on my pillow, I often put my hand between my head and the pillow situated so that my ear is between my thumb and index finger. If my hand is completely relaxed, I don't hear anything other than ambient noise. If I flex my fingers even slightly, I hear a sort of white noise. It's very faint. Where is this noise coming from or what's causing it? If I'm not mistaken, muscles are making constant adjustments to the force it takes to perform a task. So would this be the result of that benign tremor? Dismas|^(talk) 06:32, 16 December 2014 (UTC)

It sounds like the seashell effect. But have you been diagnosed with a benign tumor? ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:12, 16 December 2014 (UTC)

Do ignore the diagnosis above, which is worth considerably less than what you paid for it. I experience the same thing, as do the authors of [6]. Wnt (talk) 11:27, 16 December 2014 (UTC)

What diagnosis? ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:43, 16 December 2014 (UTC)

I'm not sure but I think i know the sound you are talking about, I always thought it was something to do with blood flow. The thing about your ear is that it is incredibly sensitive! It has been demonstrated that for you to detect a sound, air pressure has to deflect your ear drum by a distance LESS than the diameter of a hydrogen atom! Imagine that! So if you are lying in a very quiet environment, lying on your arm, I can sort of imagine that by flexing your fingers you are constricting the blood vessels slightly causing the blood to "rush" through the blood vessels making a very slight noise, possibly not even transmitting through the air, but through the material between your hand and you ear. Vespine (talk) 21:58, 16 December 2014 (UTC)

Citation needed for the "hydrogen atom" thing, please. --65.94.50.4 (talk) 02:09, 17 December 2014 (UTC)

I think Wnt is wondering why you suddenly mentioned a benign tumour which is very weird unless perhaps you misread Dismas mentioning a benign tremor as as a benign tumour. Nil Einne (talk) 14:34, 17 December 2014 (UTC)

• For the record, the OP's experience is a perfectly normal human experience. See Seashell resonance and Occlusion effect for some related articles. --Jayron32 15:34, 17 December 2014 (UTC)

Yikes! You're right. I need new glasses. Or maybe my brain wasn't expecting to see a term like "benign" next to "tremor". What exactly is a "benign tremor"? ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:25, 18 December 2014 (UTC)

Well if it helps, I actually made the same mistake and was nearly going to reply saying that perhaps Wnt missed the part where a benign tumour was mentioned until I noticed it wasn't. In my case I do definitely need new glass because my are scratched and falling apart (have an appointment with an optometrist early next year). But I don't think this was the cause, although I had read the bit about benign tumour already which may have influenced what I read. Nil Einne (talk) 19:45, 19 December 2014 (UTC)

Citations for the hydrogen atom thing. Vespine (talk) 00:08, 18 December 2014 (UTC)

@Dismas: It seems very likely that several things may be happening simultaneously here as other replies indicate, but the 'white noise' you possibly perceived when you flexed your fingers is real and originates in the myofibrils of your muscle fibres. "The sound produced by a muscle comes from the shortening of actomyosin filaments along the axis of the muscle. During contraction, the muscle shortens along its axis and expands across the axis, producing vibrations at the surface." [7] @ newscientist.com. A very technical reference [8] @ biomedical-engineering-online.com. However I am not certain that this is loud enough, or of such a frequency, as to be heard by ear. It's possible that the blood flow changes noted earlier by Vespine would drown it out. Link to a recording of muscle 'sound' here.
wp:WHAAOE! See Phonomyography. 220 of ^Borg 02:32, 20 December 2014 (UTC)

Thank you, everyone, for the great links and explanations! @Baseball Bugs: See benign tremor and simply tremor. Dismas|^(talk) 02:40, 20 December 2014 (UTC)

physics

summerfield model — Preceding unsigned comment added by 199.190.45.185 (talk) 07:56, 16 December 2014 (UTC)

What is your question? AndyTheGrump (talk) 07:59, 16 December 2014 (UTC)

Sommerfeld model? --Wrongfilter (talk) 08:24, 16 December 2014 (UTC)

Yes, five. Plasmic Physics (talk) 09:19, 16 December 2014 (UTC)

Good answer. I think you nailed it. Richard-of-Earth (talk) 20:05, 16 December 2014 (UTC)

Are you quite sure it's not four point nine repeating? μηδείς (talk) 06:58, 17 December 2014 (UTC)

It is four point nine repeating, but only on Wednesdays. Plasmic Physics (talk) 07:53, 17 December 2014 (UTC)

Mumps

1. Before the mumps vaccine, what percentage of the population had a bout of mumps in childhood? (Data for any country will do) 2. What percentage of people who have had actual mumps (not vaccination) gain lifelong immunity to the disease? Thanks. 184.147.124.158 (talk) 12:37, 16 December 2014 (UTC):

You can take your pick of which population population. The World Health Organization -Data and statistics has it all. Also, I don't think its certain (beyond all doubt) that naturally acquired Mumps gives truly life long immunity. It is certainly not the case with chickenpox and some other viruses where the individual used to have their immunity reinforced by coming into contact with the virus again and time again throughout life. Hence, adults are now getting some diseases at an age where serious complications can set in.--Aspro (talk) 22:39, 16 December 2014 (UTC)

"Natural infection was once thought to confer lifelong immunity, but we now know that reinfection can occur, although it tends to be milder and more atypical than in primary infection."[9] --Modocc (talk) 00:06, 17 December 2014 (UTC)

Thank you both for the links. How do I use them? I couldn't see mumps on the World Health page so I clicked on Immunization but it only talks about pertussis and measles. Can you tell me where you found the mumps Aspro? And Modocc, the data in that link is hard for me to parse. They seem to have picked out the same numbers of infected and non-infected people so I don't understand how to get the percentage who actually have immunity, can you explain? Thanks again. 184.147.124.158 (talk) 01:20, 17 December 2014 (UTC)

Whoops sorry. They will either refer to mumps as viral parotitis or epidemic parotiditis. --Aspro (talk) 03:02, 17 December 2014 (UTC)

The CDC states here that "Before the U.S. mumps vaccination program started in 1967, about 186,000 cases were reported each year." Since the US population then was around 190 million the percentage was approx. a tenth of one percent or one per thousand [per year. See below]. I'm not sure which study you are referring to, but the text I quoted is referenced to a study [10] that simply found evidence for recurrence by comparing 82 patients with possible recurrent mumps with an equal number of primary infected patients. That won't be much help though for estimating lifetime immunity for the various strains. --Modocc (talk) 03:11, 17 December 2014 (UTC)

Ditto. If the OP is referring to this paper then one will not be able to get the percentage as this was not what this study set out to discover.Both groups 1 & 2 of 82 individuals each showed symptomatic evidence of mumps so one must conclude that all where infected. The point was that the first group had low IgM. This suggest that they had previously had mumps before – as IgM is mainly involved in the first nouveau infection (don't quote me on all this, as these days I can't remember what I had for breakfast this morning). For subsequent infections IgM production is lower. Also, the cohort (group 4) of just 20 non-infected mumps-immune subjects was too small a sample from which to come up with a reliable figure. Without reading the full paper I can't even say how the immune cohort of 28 was selected (i.e., immune by inoculation or natural). I doubt if anyone has done such a study yet due to the cost. My advice is to just stay away from all kids – they are virus factories running at full production 24/7.--Aspro (talk) 04:06, 17 December 2014 (UTC)

I know things here in WP are meant to be referenced, and I have no reference to cite. But "approx. a tenth of one percent" is way off. When I was at school (in England, around 1960) every few years a wave of mumps (likewise chickenpox, measles) would sweep the school, infecting almost every pupil who had not already had it. It meant a few days in bed, with mild discomfort, but no lessons! And no "cases were reported". Maproom (talk) 09:01, 17 December 2014 (UTC)

The problem is that @Modocc: compared the number of people who had mumps each year with the total population, which doesn't tell you how many of that population had it over their lifetime. Back of the envelope approximations could be made from that figure and the average lifespan (i.e. multiply the number of cases per year by the average lifespan of a person, compare to the population), or comparing it to the birth rate (i.e. mumps cases per year / new people per year), but neither seems likely to be particularly accurate. MChesterMC (talk) 09:18, 17 December 2014 (UTC)

Whoops, I was half asleep (I still am) and missed the "in childhood' part of the question. Even if young children primarily got it and made up ten percent of the population (increasing the percent per year by a factor of ten), then for fifteen consecutive childhood years per person that adds up to only a childhood infection rate of only about fifteen percent. I don't know the reason why that is so low and only have guesses as to why. For instance, kids might have been asymptomatic or were only mildly sick and stayed home and did not see a doctor, such that these cases went unreported as Maproom suggested. Alternatively, again I am only guessing here, localized herd immunity perhaps created bottlenecks along major travel routes that may have hindered its spread. -Modocc (talk) 11:05, 17 December 2014 (UTC)

Thanks for the followups, much appreciated. Clearly this data is pretty hard to find. I will keep looking under the latin terms, if anyone does come up with the numbers please keep posting! 184.147.124.158 (talk) 11:55, 17 December 2014 (UTC)

Is it known which drug is with the longest half life

5.28.177.164 (talk) 12:53, 16 December 2014 (UTC)

"Half life"? ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:41, 16 December 2014 (UTC)

See biological half-life. The article lists some examples (Bedaquiline with 5.5 months, e.g.), but that's probably not the record-holder (also, see the metals) . All the "longest half life" items I googled in connection with drugs meant the longest within a certain group or sample of drugs, not of all known drugs. ---Sluzzelin talk 16:47, 16 December 2014 (UTC)

(edit conflict) Half-life is the standard way to analyze how a drug is metabolized and excreted in your body, since the measurable levels of the compound in your body will degrade in power law manner, you can calculate a drug's half-life. It's rudimentary stuff. I don't know the answer to the OP's question, but will direct him (and anyone who wants to read more) to the article on pharmacokinetics, which is the study of how the body processes a drug. Half-life is a very common measurement for a drug's presence in your body. --Jayron32 16:49, 16 December 2014 (UTC)

Why wouldn't Mcdonald's French Fries rot?

I've seen some videos comparing Mcdonald's French Fries and home made ones. It seemed that Mcdonald's French Fries rot slower than homemade ones. Is it just because Mcdonald's French Fries has too much salt and too little water (in comparison the home made French Fries with large cross section[11] seems to rot faster than those with small cross section[12])? Or is it because Mcdonald's French Fries contains some artificial preservatives?--Bdog07 (talk) 13:32, 16 December 2014 (UTC)

Do you mean literally rotting, or simply becoming no longer tasty? ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:42, 16 December 2014 (UTC)

(edit conflict) Salt is a perfectly good preservative. I have no idea what the methodology is behind those videos, but this is why you don't trust random youtube videos. There's far too many opportunities for someone to screw up the experiment, either unintentionally (for example, not salting the homemade fries to the same level as the McDonald's fries) or intentionally (because they have an axe to grind, see Super_Size_Me#Criticism_and_statistical_notes for how these things can go wrong). A random youtube video is NOT a controlled experiment, and should not be trusted one way or the other. I am not saying the people are lying, I am not saying the video is or isn't an actual experiment. What I am saying is there is no way to draw any meaningful conclusion from it because we can't trust the provenance or methodology or anything from it. So, we can't answer your question because we don't know if the videos are trustworthy, and as such, there's no need to explain why they are happening that way. You've started with the conclusion that the video maker has planted in your head, instead of starting with "can I trust the video one way or the other". If you can't answer THAT question to a satisfactory level, you can pretend you never saw it... because it means nothing. --Jayron32 16:45, 16 December 2014 (UTC)

(edit conflict) They dry out before they can rot. The large surface area to mass ratio and water boiled off during frying combine to make this happen. If you were to keep them damp, then I suspect they would eventually rot. StuRat (talk) 16:46, 16 December 2014 (UTC)

I found McDonald’s Reveals 17 Foul Ingredients in Their French Fries, which if true, says that they use citric acid as a preservative amongst all the other stuff. Mmmm... Alansplodge (talk) 16:57, 17 December 2014 (UTC)

That site looks about as far from a reliable source on health matters as you can get. I think citric acid is pretty benign as food additives go - it's a major part of lemon juice, after all. AndrewWTaylor (talk) 17:23, 17 December 2014 (UTC)

Apologies, I was being lazy. Here is the ingredients list for the fries sold in the US (p.14): "FRENCH FRIES: Ingredients: Potatoes, Vegetable Oil (Canola Oil, Soybean Oil, Hydrogenated Soybean Oil, Natural Beef Flavor [Wheat and Milk Derivatives]*, Citric Acid [Preservative]), Dextrose, Sodium Acid Pyrophosphate (Maintain Color), Salt. Prepared in Vegetable Oil: Canola Oil, Corn Oil, Soybean Oil, Hydrogenated Soybean Oil with TBHQ and Citric Acid added to preserve freshness. Dimethylpolysiloxane added as an antifoaming agent. CONTAINS: WHEAT AND MILK. *Natural beef flavor contains hydrolyzed wheat and hydrolyzed milk as starting ingredients...".

Interestingly, McDonald's don't put any of that stuff in the fries that they sell in the UK: "Fries: Potatoes, Vegetable Oil (Sunflower, Rapeseed), Dextrose (only added at beginning of the potato season)." No idea why that is. Anyhow, perhaps the citric acid (harmless as it is) helps explain why their fries last longer. Alansplodge (talk) 22:18, 17 December 2014 (UTC)

Can you "see" a cell-phone probing for a network?

In the same way you can see a PC probing for a wlan?--Senteni (talk) 17:30, 16 December 2014 (UTC)

From a purist, physical scientific standpoint, "yes." Mobile telephones actively transmit radio frequency signals, and you could theoretically detect and decode such transmissions.

In a practical sense, "no," you can't buy the gear you need to break the encoding - or even to demodulate the radio signal in the most commonly used mobile telephone spectra.

With sufficient domain-specific expertise, and certain very expensive equipment, it is evidently possible - somebody is designing, building, and testing telephones! But those tend to be very large telecommunications companies who employ large numbers of highly-specialized engineers. There are many hobbyists who attempt to build their own cheaper "cellular"-band sniffer radios, and in principle this can be done - heck, when I was in graduate school we built UHF radio mixer-transceivers out of copper tape and single transistor amplifiers ... but to do this efficiently requires a lot of time, money, and experience. If you go down to your neighborhood HAM radio store, and dig around among the pretty high-end gear, you'll invariably find an abrupt "band-gap" in the available equipment right at the frequencies you might find interesting. A lot of times, you'll see this in the product marketing literature as a radio with "ultra-wide band (less cellular)." For example: The Alinco DJ-X30T wideband receiver covers 100 kHz to 1299.995 MHz (less cellular). But click around on the more expensive gear - no matter how much you spend, you can buy radio equipment in any band you want (less cellular). It's almost as if ... the Government forbids mere mortals from purchasing or using equipment that would interfere with common-use radio spectrum, ensuring that electronic surveillance isn't easy or cheap! In the U.S., you could probably get away with receiving signals passively, as long as you never transmitted... but in other countries, like the U.K., even a passive receiver may be illegal to operate.

Unlike IEEE 802.11 frequencies, mobile telephones operate in radio bands that are much more tightly regulated, which means that you cannot easily and cheaply buy electronic test equipment that receives or transmits in those bands. This is a good thing for the digital-radio-using public: it is just one of the many technical and administrative hurdles that prevent unauthorized hobbyist "eavesdroppers", "jammers," and other troublemakers from interfering with mobile digital radio.

Nimur (talk) 17:45, 16 December 2014 (UTC)

You can easily and cheaply hear the characteristic interference that mobile phones create in the reception of Longwave AM broadcasting such as BBC Radio 4 in the UK. Of course, you would need very different and much more expensive equipment to decode the signals. Dbfirs 21:38, 16 December 2014 (UTC)

This is an alternative link to Title 47 § 302a, for anyone having difficulty using Nimur's link. Tevildo (talk) 23:01, 16 December 2014 (UTC)

(Technically, you have linked to United States Code, Title 47; I linked to Code of Federal Regulations Part 47. These are parallel but distinct sets of laws and they serve different purposes; items in USC are codified statute law, while CFRs are federally-enforceable administrative regulations; CFRs tend to be a lot more specific but a lot less fun to read).

Nimur (talk) 02:18, 17 December 2014 (UTC)

Ah, sorry. I can't get your link to work at all, so I guessed what it referred to based on the URL. The precise text of the legislation is probably irrelevant here. Tevildo (talk) 09:23, 17 December 2014 (UTC)

Yes. The point is that cellular radio equipment is not easy to legally purchase, because it is tightly regulated. Anybody who legitimately needs to know more will know where to look. Nimur (talk) 15:49, 17 December 2014 (UTC)

I'm unconvinced it's as difficult to buy equipment capable of receiving those signals as you suggest. Various sources like [13] [14] [15] [16] [17] [18] [19] [20] suggest you can probably at least detect (which seemed to be what the OP referred to), if not even decode (I'm actually a bit surprised by this, I didn't quite expect the RTL-SDR to be good enough for that level) a number of mobile phone network signals using a simple RTL-SDR. I don't want to comment much on the legal issues but I'm fairly sure owning a DVB-T stick with the RT2832U chipset would be legal in much of Europe including the UK where DVB-T is common. And definitely these are easily available on places like Ebay and Amazon for under US$20 or less, including from local sellers. I'm not totally sure if these are legal in the US since DVB-T isn't used there but since as was mentioned, the legal restrictions on devices only capable of receiving are generally far less stringent it wouldn't surprise me if they were and they can definitely be purchased from sellers in the US. Of course, just because it's legal to own and use the device for its intended purpose doesn't mean it is to use the device for other purposes, particularly monitoring frequencies associated with mobile phone networks [21]. But the point remains, legally buying and owning equipment capable of at least detecting the signals probably isn't as difficult as you suggest even if actually doing it could theoretically get you in to trouble. BTW, as also highlighted a previous time this came up another option which isn't that cheap but also isn't super expensive is a USRP (the sited figure was around ~$1200) combined with an appropriate daughterboard like [22] (specifically advertised as being suitable for such purposes). I have no idea however how easy this is to buy in the US but the seller has existed for a while now without any apparent major problems despite some confusion last time. (Of course my early point stands that just because you can own it doesn't mean you can use it for the purpose without theoretically getting in to trouble and if you're actually transmitting rather than receiving, it may be more than theoretical. Then again, transmission was never mentioned by the OP.) Nil Einne (talk) 17:57, 18 December 2014 (UTC)

The first problem you will run into is interference. Cell phones trying to make a connection use the same radio frequencies as are used for communication. So unless you are out in the wilderness or inside a faraday cage you are going to have a hard time picking out the signal you want. If you are isolated I imagine you would be able to 'see' the signal with radio receiver that can tune to the required frequency and an oscilloscope to display the signal. You won't be able to decode the signal with that kind of setup, but you should be able to tell if the cell phone is transmitting. If you want to decode the data, then Software Defined Radio [23] is the rat hole you need to crawl into. — Preceding unsigned comment added by 50.43.56.168 (talk) 09:18, 17 December 2014 (UTC)