Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

stargazine_ep28_banner.thumb.jpg.b94278254f44dd38f3f7ee896fe45525.jpg

MeanEYE

Making A Radio Telescope

Recommended Posts

Hi there folks. Am not sure if this is the right place to post this topic but hopefully admins will move to a better place if I did make a mistake.

For a while now I've been thinking about creating my own radio telescope around 2m in diameter. I did some preliminary search online and found all sorts of results so I decided to ask here. Am not interested only in measurements but imaging as well. When answering please bare in mind that I am pretty new with the whole astronomy hobby.

Okay, my questions are:

  1. Do you know about already made kits which can be purchased?
  2. Any useful links I should see in case I decide to make everything on my own?
  3. In case I do decide to make everything on my own, are there ready made sensors I can purchase?

As I am a programmer I thought it would be cool to perhaps share live data stream online or perhaps enable some sort of remote control so more folks can benefit from this little project of mine. I would probably do all the programming myself.

Thanks in advance for your answer and patience.

  • Like 1

Share this post


Link to post
Share on other sites

No worries, looks like a fun project and I'm going to have a stab when I get some spare time ...

Share this post


Link to post
Share on other sites

I was kind of joking the other day when I suggested to my wife, that what I needed with all this cloud, was a radio telescope.

Now then.... Where did I put that old satellite dish.....?

:)

Will keep following this thread to see what happens.

  • Like 1

Share this post


Link to post
Share on other sites

Ah!! They work through clouds, do they? Thought the water content might block the signals. If they do that's really interesting :D How lovely it would be to have something that works on cloudy nights :)

  • Like 1

Share this post


Link to post
Share on other sites

I was kind of joking the other day when I suggested to my wife, that what I needed with all this cloud, was a radio telescope.

Now then.... Where did I put that old satellite dish.....?

smile.gif

Will keep following this thread to see what happens.

Think i'll have to get some old sat dishes think me dads got one in his shed and get couple of LNB's

wont have clue what to do next like someone have to make rest :)

my computer systems on all time so would have it running 24/7

Share this post


Link to post
Share on other sites

I have seen a few things about old satellite dishes, but they're only really sufficient for detecting large apparent diameter objects like the moon and Jupiter and the Sun.

This got me thinking, and if we have a programmer in the house it might help the thinking process along:

Same as the problem faced by governments really, but on a smaller scale, constructing a massive dish is beyond the means of most of us. However, what about some VLBI (Very Long Baseline Interferometry)?

If a number of us were to purchase 3 or 4 satellite dishes each, would we then be able to link them up via the tinterwebs and create a virtual dish with an effective dish size correspondent to the largest separation between the dishes? When not hooked up, 4 dishes would make a bit of backyard fun, but all linked together, we could have our very own, full sized SGL Radio Telescope.

It would be a bit of a challenge to firstly get the individual dishes set up and working, and even more of a struggle to get the virtual dish going, but surely it can be done?

If people would be interested, I'm sure I could approach the department at uni and get some professional help? I know one of my lecturers does RA, so I'm sure he'd be willing to give some guidance?

Just a thought, anyway. Maybe I'll set up a new thread, if I get any interest....?

Share this post


Link to post
Share on other sites

I'm always interested in revolutionary projects but fear this would be beyond my means financially. We have a fair amount of space. The project would certainly interest me even if it's only as a spectator - though it would be nice to get involved.

Oh dear.... I'm at it again... finding extra things to do as if I hadn't got enough already :D Watching doesn't take too much time though :)

Share this post


Link to post
Share on other sites

TBH Gina as far as I understand the thoery, only 1 dish would be necessary to participate in an SGL-wide project, and they're only about 2 feet by 1 foot by 2 feet high. Wouldn't even have to remain in place at all times, could be tidied away when not in use if it had to be, as long as it was placed in the same place in the same orientation at all times.

Anyway, such a project would be some time in the making and could presumably be joined / left at any time, so it's not as if you'd have to commit to anything!

Share this post


Link to post
Share on other sites

Thanks :) Put me down as definitely interested :)

Share this post


Link to post
Share on other sites

So... you need a dish, a mount for it and a sensor. I imaging a large satellite dish would be suitable. The mount is pure mechanics with motors as we all know well about - I could make that. But what do we use for a sensor. Satellite broadcasts just need a little aerial and receiver but if we want images it would need a receiving array just as we have an array of light sensors in a camera. I imaging the frequency band (or wavelength) is a lot higher than satellite broadcasts (shorter wavelength) if we want any sort of resolution out of a dish a few feet across. As I recall radio telescopes use highly cooled sensors - I wonder how well we could do by going down to a mere -20C or so.

Another point... the dish would need either to be very rigid and strong with mount to match or housed in a radio transparent dome or something.

Share this post


Link to post
Share on other sites

From what I remember seeing, the sensor built into satellite TV dishes was used as the antenna array. However, I'm not sure whether this would be suitable if we wanted to image smaller / fainter objects.

Wavelength would indeed be very long - whence why we would need a number of widespread dishes to achieve a decent resolution.

As for cooling, I've seen your work with Peltiers - maybe you could be our sensor cooling expert? :D

I've started a new thread about this Gina, so as not to hijack this original thread! It is here:

Share this post


Link to post
Share on other sites

From what I remember seeing, the sensor built into satellite TV dishes was used as the antenna array. However, I'm not sure whether this would be suitable if we wanted to image smaller / fainter objects.

Wavelength would indeed be very long - whence why we would need a number of widespread dishes to achieve a decent resolution.

As for cooling, I've seen your work with Peltiers - maybe you could be our sensor cooling expert? biggrin.gif

I've started a new thread about this Gina, so as not to hijack this original thread! It is here:

http://stargazerslou...ronomy-network/

How do you image stuff with satelite dish interesting.

Share this post


Link to post
Share on other sites

I would most certainly be interested in doing radio astronomy as well, if only I knew how to go about it - would pass those cloudy dats and nights a treat.

Share this post


Link to post
Share on other sites

I could be up for this, too...

Couple of questions...

1. we are not all going to able to connect to the same data store at the same time (even different cable lengths to the exchange and withing the internet will be enough to knock the results out), so we will need to find a very accurate clock and include it in all signals. The only obvious thing I can think of is the GPS time signal - has a few issues but could be usable?

2. alignment might be a bit of an issue. Even with a powerful, local source (the Astra satellite - does anybody else get visions of a knackered Vauxhall in geostationary orbit when they hear this?), even a very small angular error meant next to no signal. Anyone have any idea what degree of accuracy we will need or how to achieve it?

  • Like 1

Share this post


Link to post
Share on other sites

These are excellent points jamespels, would you be kind enough to echo them at:

Yes I definitely agree about timing. I think it would be neccessary to contact a proffesional body about this. Do you have any idea how accurate the timing would have to be?

As for alignment, I would presume that it would be neccessary to connect the mounts to a central server to ensure that the alignment was cohesive, i.e. all mounts were pointing in the same direction at the same time. I guess this would be a progeamming issue rather than a construction issue? In that if all dishes were connected with some relatively basic goto equipment plus maybe some gps it could be coordinated?

Share this post


Link to post
Share on other sites

Ooohhhh.....

I'm liking this. An amateur Very Large Array.

Count me in!

Share this post


Link to post
Share on other sites

I'm only a beginner.. But i really want to be involved...I'm in if you will have me...Will i need one of these?..http://www.maplin.co.uk/satellite-finder-48325

Edited by Vince1963

Share this post


Link to post
Share on other sites

How do you image stuff with satelite dish interesting.

'Imaging' might not be the right word, sorry, I suppose I used it out of simplicity. From what I gather, you build up an intensity map of a certain region of sky, so it does end up as a kind of image, but not in the sense we're all used to!

Share this post


Link to post
Share on other sites

At this stage, I think anyone with a good idea should contribute - it is going to take a lot of combined skills to make this work...

Also, the more dishes we can spread out over as wide an area as possible, the better.

J.

  • Like 2

Share this post


Link to post
Share on other sites

One of the sites I looked at linked to in this thread mentioned a Euoropean setup (I think) that used Satellite TV line time-base 15.6KHz signal and PLL system to get very accurate timing. This is entirely possible and would just require a satellite TV receiver and dish to receive the TV signal - plus some home made circuitry. GPS is nowhere near accurate enough apparently.

Edited by Gina
  • Like 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.