Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

athornett

Members
 View Profile  See their activity

  • Posts

    266

  • Joined

  • Last visited

 Content Type 

Posts posted by athornett

    Making a hydrogen line Cantenna

    in Radio Astronomy and Spectroscopy

    Posted

    At last I am having a go at making myself a Cantenna (a type of aerial made using old tin can - in this case designed to detect hydrogen on 1420MHz in Milky Way)! If this works it will demonstrate that I can make a full hydrogen line radio telescope for < £100!

    This would be a great project to offer members of my local astronomy group.

    Andy

    Click on link to see photos of my project:

    https://astronomy.me.uk/making-hydrogen-line-1420mhz-cantenna

    • Like 2

    Why everyone needs a banana in their kit box.....

    in Radio Astronomy and Spectroscopy

    Posted

    Yes I presented at Astrofest. I am trying to encourage people to consider alternatives to traditional amateur astronomy. Yes I bought these detectors - which is why I wanted to tell people about them.  I am in process of conducting range of other experiments with them - just haven't posted on those yet! More information on how they work and detect muons from cosmic rays available at CosmicWatch::catch yourself a muon (mit.edu)

    Andy

    pointing with a radio telescope?

    in Radio Astronomy and Spectroscopy

    Posted

    NB Although previous posts have commented on large field of view of radio telescopes, I have noted that I can see gaps on my Milky Way hydrogen map with my 86 x 86cm array (equivalent to roughly 86cm dish so not big) when my changes in declination are > 5 degrees. However this is question of neatness of the map - I don't need this much detail to either map spiral arms of Milky Way or to demonstrate existence of dark matter, both those observations being quite resilient to variations in equipment used (some people have even used a tin can as their aerial!)

    Andy

    pointing with a radio telescope?

    in Radio Astronomy and Spectroscopy

    Posted

    You have had lot of detailed responses above.

    Simplistically, the options for small radio telescopes are:

    1. You point the telescope in one direction at particular declination then leave the rotation of the Earth ro bring different parts of the sky into field of view of the telescope. The declination can then be varied to cover more of sky. I just point it and then use inclinometer to find out what angle I have got. I use this method on my dipole array see www.astronomy.me.uk

    2. Small dishes can also sit on EQ6 mounts as long as they are light. Ideal for msh dishes (ie not solid ones) due to weight and effect of wind blowing on solid dishes. Bear in mind relatively large efeect of small weights far away from fulcrum. Also problem here is that radio telescopes left out all time and astrophotography mounts do not tend to like rain amd snow on them!

    3. Purpose built rotators and directional finders, difficult to buy over the counter, so usually hand-built by amateur themselves.

    Andy

    • Like 1

    The "AERIAL Man" commeth (a wibble!) :P

    in Radio Astronomy and Spectroscopy

    Posted

    I have seen people succeed with Yagi antennae at 1420.405Mhz.

    In my experience these observations are very sensitive to how well tuned the aerials are to this frequency.

    The obvious question with your Yago is if you point it at Milky Way and then away again what happens to this strong signal you describe.

    Also what happens if.you replace aerial with 50 Ohm dummy load?

    Also what software you using and what SDR or other radio?

    Are.you calibrating the signal using dummy load or other metho

    Andy

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.