Can a TV antenna pick up cosmic radio waves? - SETI Style Distributed Radio Telescope (DRT), is it p

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Mee_n_Mac

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<p>And the UHF band in the US runs from about 470 Mhz to about 800 Mhz with the region form 608 - 614 reserved for radio astronomy !&nbsp; Alas that reservation only works in the US and Canada, Europe uses that band for "stuff" so it won't be quiet worldwide. </p><p>I guess in this endevour it would be helpful to get the gist of what you want to do. I don't think ganging up all the available TV antennae is going to make a super good receiving station capable of listening to the universes faintest whispers.&nbsp; You might, with a lot of work, get a high resolution system capable of making detailed maps of strong radio emitters though I don't know just how good it really could be and whether the result would be worth&nbsp;the effort.&nbsp; Maybe someone could tell us how we presently do worldwide VLBI and then "we" could see how applicable that method is to your TV network.</p> <div class="Discussion_UserSignature"> <p>-----------------------------------------------------</p><p><font color="#ff0000">Ask not what your Forum Software can do do on you,</font></p><p><font color="#ff0000">Ask it to, please for the love of all that's Holy, <strong>STOP</strong> !</font></p> </div>
 
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BoJangles

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<p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">That&rsquo;s something I really have never thought about in depth. The maximum resolution obtainable by such an array would come down to the smallest signal the technology is capable of receiving per base station (the weakest link type of analogy). I.e. In regaurds to the TV antenna, coaxial cable, and the hypothetical hardware, the array would only be capable of sharpening an image of the weakest theoretical signal it could receive. </font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">I suppose that depends a lot on the inherent limitations of the average antenna, coax, combined with the amplifiers and technology that is converting RF to a computer friendly output.</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">I guess the more effort that went into the amplifier side of things, the better the weakest link would be but as people have previously mentioned, that maybe fairly limited on small budgets.</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">---</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">If the antennas are getting swamped by terrestrial radio signals (such as normal TV stations), it should be theoretically possible to completely and effectively mask them out via cross-referencing data over large a geographical area.</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">Let&rsquo;s take a hypothetical array that spans parts of Canada, the US, and Hawaii. Data can be masked over a large geographical area. For instance, comparing the data sets of base stations 5 kms apart, wouldn&rsquo;t really be very useful. But comparing data sets between base stations over 500 kms would clean up terrestrial signals very effectively (that&rsquo;s assuming they aren&rsquo;t playing sex and the city, at the same time on the same frequencies, in Canada the US and Hawaii at the same time).</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">Even the smallest noise from cosmic sources would be left alone (isolated), because in effect they would be consistent over very large areas; unlink your neighbour using his band saw, or a TV station playing their usual brain numbing tripe.</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">Unfortunately, earth orbiting satellites would be an exception to this, and would have to be cleaned up after the fact, but there are a couple of tricks that could be used to solve this as well. </font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">I think the main problems here is, what would this array be useful for, and what are the theoretical limitations of these dipole antennas.</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">---</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">Do you think we should be putting this under a new thread? It would be great if we could start a whole topic on this in these forums somewhere, so multiple discussions lines could be started on the same topic and additionally a general overview of the concept could be easily at hand ( opposed to buried in this thread ), maybe one of the moderators could help us out with this ?</font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">Topic name could be &ldquo;Distributed Radio Telescope (DRT)&rdquo;</font></p> <div class="Discussion_UserSignature"> <p align="center"><font color="#808080">-------------- </font></p><p align="center"><font size="1" color="#808080"><em>Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog.  With that out of the way, I have several stupid questions... </em></font></p><p align="center"><font size="1" color="#808080"><em>*** A few months blogging can save a few hours in research ***</em></font></p> </div>
 
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Joveno

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Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>My question is specifically related to the capability of an average TV antenna, on an average roof top, in an average configuration, to pick up non terrestrial radio waves.Now I realise TV antennas are directional and they are optimised for things like sex and the city coming from your local radio tower. But what I specifically want to know is, assuming you could &ldquo;magically&rdquo; remove the interference from terrestrial radio sources, could that aerial be used to pick up cosmic radio frequencies.I&rsquo;ll put some constraints on this question, which are as follows; &nbsp;we are using an average TV antenna, it is connected to coaxial cable (like most TV antennas), I have magic that can remove &ldquo;all&rdquo; terrestrial interference(or we lived in a radio dead world), I have a $1000 budget to buy and build amplifiers and the appropriate electronics to connect my antenna to my computer, I do not need any triangulation or directional information in regards to the frequencies (just a graph).I would assume if any signal could be picked up it would be very faint ( due to the configuration and design of the average TV antenna), but all I really want to know is the capability of a normal TV antenna in a normal configuration to receive the right frequencies needed to listen to things from outside the earth.Answers I would expect to get are. TV antennas cannot pick up the right frequency range (they just can&rsquo;t), or the atmosphere would kill any chance of using a TV antenna in that way. Or sure you could probably pick up the right frequencies but they would be so small your $1000 budget would have no chance of enhancing them enough for useful science. Or sure that sounds possible but you would definitely need a radio dead world or magic to cancel out interference.Thanks for any response in advance&nbsp; <br />Posted by Manwh0re</DIV><br /> <div class="Discussion_UserSignature"> </div>
 
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Joveno

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> <br />Posted by Joveno</DIV></p><p>If you could magically remove terrestrial inference, you probably wouldn't have much left because rooftop television antennas are specifically designed to pickup VHF/UHF signals that constitute the television spectrum.&nbsp; Now when broadcast TV goes digital, this might change, but there will still be plenty of traffic on the old TV spectrum to make such antennas poor choices for detecting anything other than terrestrial noise.&nbsp; Oh well...<br /></p> <div class="Discussion_UserSignature"> </div>
 
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MeteorWayne

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<p>Somewhat off topic....</p><p>http://www.nrao.edu/whatisra/hist_jansky.shtml</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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BoJangles

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Somewhat off topic....http://www.nrao.edu/whatisra/hist_jansky.shtml <br />Posted by MeteorWayne</DIV><br /><br /><font size="2">Interesting all the same.</font></p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p align="center"><font color="#808080">-------------- </font></p><p align="center"><font size="1" color="#808080"><em>Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog.  With that out of the way, I have several stupid questions... </em></font></p><p align="center"><font size="1" color="#808080"><em>*** A few months blogging can save a few hours in research ***</em></font></p> </div>
 
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