47 replies to this topic

[Am33r]

The second coax port on the currently installed LNB connects to this SDR setup. I tried the software with a laptop and it's fine, but I will start messing around with Android-based apps and see what I can get.

[robin_astro]

Sun and Moon with my similar setup

http://www.threehill...astronomy_1.htm

 

Cheers

Robin

[Am33r]

Sun and Moon with my similar setup

http://www.threehill...astronomy_1.htm

 

Cheers

Robin

Incredible!

You sir are my new best friend (= I'm coming with a lot of questions soon

[robin_astro]

Incredible!

You sir are my new best friend (= I'm coming with a lot of questions soon

It looks like you have already got as far as I did.  It is possible to make Milky Way Hydrogen line measurements with a small dish but because the  Hydrogen line wavelength is ~10x longer than the modern satellite TV lnb receives the resolution is very low. Good enough to see the arms of the Milky Way though. There was an interesting thread on this on another forum that I was following. (It is very long and rambling but this link shows the setup and there are full details elsewhere in the thread)

https://stargazerslo...comment-3508554

 

I acquired a 1.8m dish with the idea to so something similar but never got round to building it.

 

Cheers

Robin

Edited by robin_astro, 15 May 2020 - 09:12 AM.

[Am33r]

So what If I keep the dish but get a diff feed horn.

Yea, that's a good one, a lot of work too!

 

Here is another one with around 1 meter dish, which I can mount onto a little larger Meade fork mount.

 http://www.sbrac.org...o_telescope.pdf

 

It is also stated here

 https://www.rtl-sdr....adio-astronomy/

 

Ideally, I will build that next:

With a Larger Mount (maybe a Meade LX200 mount, and a 90cm Dish, and a Laptop.

You can have a few LNBs / Feed Horns that can clip onto the focus in the Dish's tripod and you can switch your observation from one thing to the next all with one radio telescope.

 

Kind of like how we do it with an optical telescope when with one telescope we replace eye pieces, white solar filters, hydrogen alpha filters, etc. and observe different things all with one telescope but different parts are added.

Edited by Am33r, 15 May 2020 - 08:57 PM.

[Am33r]

Oh this looks like it will be a fun project..

You can build a VerySmallArray when you get 4-5 more dishes and mounts..

Sounds interesting, I have a few dishes, and with those particular mounts (if I end up making more) I can synchronize them as they track.

But what exactly can I do with the data that 4 dishes give, instead of 1

[TxStars]

You might want to read up on the VLA 

 

 

https://en.wikipedia...ery_Large_Array

http://www.swarthmor.../array/vla.html

Edited by TxStars, 16 May 2020 - 12:01 AM.

[robin_astro]

Yes multiple dishes can be combined to increase resolution but this is very tricky as you need to synchronise the signals to a fraction of the wavelength you are measuring. There are some amateurs that have done this eg

https://astropeiler.de/Interferometer

 

but I don't know offhand any amateur systems with more than 2 dishes 

 

Cheers

Robin

[robin_astro]

There are some amateurs that have done this eg

https://astropeiler.de/Interferometer

 

 

This site has a lot of other interesting information (The German amateur team operate various dishes including a steerable 25m  !)

 

For Hydrogen line ideas take a look at this page (The documents are in English)

https://astropeiler....nfachen-mitteln

 

It is amazing how even a simple antenna can be used to detect Milky Way Hydrogen, even just a dipole with a CD as a reflector 

https://astropeiler..../Hydrogen_4.pdf

figure 22

 

Robin

Edited by robin_astro, 16 May 2020 - 03:07 PM.

[Am33r]

You might want to read up on the VLA 

 

 

https://en.wikipedia...ery_Large_Array

http://www.swarthmor.../array/vla.html

Yea, but I need Huge Aperture for each to get any scientifically significant date; 4 of those 49cm Dish Antennas together won't do much, but I'm glad you showed me that page (= maybe my next project can do it.

Edited by Am33r, 17 May 2020 - 04:53 PM.

[Am33r]

This site has a lot of other interesting information (The German amateur team operate various dishes including a steerable 25m  !)

 

For Hydrogen line ideas take a look at this page (The documents are in English)

https://astropeiler....nfachen-mitteln

 

It is amazing how even a simple antenna can be used to detect Milky Way Hydrogen, even just a dipole with a CD as a reflector 

https://astropeiler..../Hydrogen_4.pdf

figure 22

 

Robin

 

Dude! I'm really happy you showed me that! look how many different telescopes were able to pick up the Hydrogen Line; even smaller ones like a CD and my current 49cm dish can do it - at resolution cost, but yes (= doable!

 

Keep the info coming man! Cheers 

[S.Boerner]

This big enough? 

 

The view is pretty good from the 432' level too!

 

(100m Robert C. Byrd Green Bank Telescope, Green Bank, WV)

Attached Thumbnails

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[Am33r]

This big enough? 

1200px-Green_Bank_Telescope_NRAO_(cropped).jpg

 

The view is pretty good from the 432' level too!

 

(100m Robert C. Byrd Green Bank Telescope, Green Bank, WV)

yea, let me start 3D printing that lol, and never finish

[S.Boerner]

In seriousness, are you using 3d printing as part of your project?

[Am33r]

In seriousness, are you using 3d printing as part of your project?

Yea, so far I created several parts you can see in the pictures, all printed in Black PLA

 

LNB Bracket

Dish-to-Mount Bracket

Hand Controller Hook

Coax Chords Glove

Dual Coax Chords Retainer

And the Power Module Box & Lid for the Satellite Finder System

 

I will be making some more parts when I put together the Case that hosts all the instruments.

Edited by Am33r, 17 May 2020 - 06:05 PM.

[jlcop]

Wow! What a coincidence, I just changed TV providers and have been staring at the old dish wondering if it would be worth the effort...

Please continue to keep us updated. This is very interesting.

John

[Observateur]

Very interesting thread. Thanks for taking the time to share.

[Jethro7]

I've been curious about this discipline. Keep us posted.

"HAPPY SKIES AND KEEP LOOKING UP" Jethro

[Am33r]

I had to 3D print some things to hold the equipment together, and now it is ready for the upcoming school year 

In the future I will add the optional replacement of a Ka LNB, and a Hydrogen Line Feed Horn; that's what the eyepiece holder on the tripod is for.

Here is my Radio Telescope X

 

 

 

 

 

 

 

Edited by Am33r, 27 June 2020 - 03:54 PM.

[Rich (RLTYS)]

This is so cool!  

[Crusty99]

Great thread on amateur radio astronomy.

 

[JoeVanGeaux]

Am33r,  this is a cool project!  Good work!

I have an extra ETX-90 mount that I repaired and have been considering options as to what I can do with it.  I thought about 3D printing an offset attachment mount to mate to it so that I can use a small refractor scope  (the offset is so I can have better access to objects high in the sky).

However, your project may just have a greater appeal.  Keep us informed of your progress!

All the best!

 

-Joe

[Am33r]

Am33r,  this is a cool project!  Good work!

I have an extra ETX-90 mount that I repaired and have been considering options as to what I can do with it.  I thought about 3D printing an offset attachment mount to mate to it so that I can use a small refractor scope  (the offset is so I can have better access to objects high in the sky).

However, your project may just have a greater appeal.  Keep us informed of your progress!

All the best!

 

-Joe

I once thought of using the mount for my solar refractor, but then I bought a used Cube-G mount for my solar scope.

I chose the 125 because it can carry 8 lbs, check on how much the 90 mount can carry, my setup in 5-6 lbs, so you shouldn't get a larger dish, just 60 cm or less.  The dish itself doesn't weigh 2 lbs but the back attachment and the LNB would add weight in awkward positions that it is difficult to balance the dish & components on the mount at the center of mass - still works fine though.