Build Your own FM Radio Astronomy Lab

Because I'm a simple man, and the thought of trying to understand all of the unknown is more than I can handle, I prefer the simpler side of astronomy. My personal astronomy tools include a 4.5" reflector telescope, a pair of binoculars, and a FM Radio! So your asking, "FM Radio?". Well... I love to tune into the oldies and listen to some Hendrix or Three Dog Night while viewing the heavens! Ha ha! No - not really. I actually love listening to static, and the occasional ping produced from 'stray' amplified radio waves. Okay... Okay... don't click on your browsers Home button or Back button just yet. Give me a chance to explain! This is something that thousands of amateurs and professional astronomers alike have started doing recently.

Hobby based observation of the heavens is harder or more difficult than most people think. A lot of things need to be just perfect to make the most of a night of visual observation.

• a clear clean sky subject to the least amount of *light pollution possible
• the weather must be cooperating - forget about visual observation when it's raining
• a full moon can increase light pollution too - unless you are observing the moon!
• generally speaking, you need "a night sky" (it's hard to visually observe during the daylight hours)

Most of all, you need patience and time. Many of the things above are beyond our control. We can't control when it's day or night and we can't control the weather. That doesn't leave us much time. Then we are at the mercy of our daily schedules to determine when we have time to relax and observe. But this isn't necessarily true of FM Radio Astronomy.

Being an astronomer isn't just about observing the heavens by using a telescope. Amateurs and professionals alike enjoy many different methods of observing the skies. As I stated earlier, FM Radio astronomy has been gaining popularity lately due to its ease and uniqueness. It's unique, due to the fact that it's not a visual observation technique, but an audible observation. For the techno-geek, it's called listening to Forward Scatter. The technique that I explain isn't for listening to the heavens, the moon, or the pulse of 'nearby' binary star. It's a technique for listening to falling meteors. That's right! You can 'listen' to falling meteors! "Why would I want to listen to meteors?", you ask? Well, mainly because it's geeky and it can be done day or night, rain or shine. Well, actually let me correct my self. You could probably listen for falling meteors during a small steady rain-shower, but it would be hard during a thunder-shower. Lightning would cause interference that would make it difficult to distinguish meteors from lightning. Andy passing-by airplanes can cause interference as well, but these are just a few of things that make this hobby so exciting. Lighting, airplanes and meteors all have their own specific audible signature mark. So for a seasoned FM Radio Astronomer, it's fairly easy to distinguish between 'interference' and an actual falling meteor.

And you don't have to necessarily listen to falling meteors. NASA recently called upon amateur and professional FM Radio Astronomers alike to volunteer. They wanted signature data from different FM Radio Astronomers to record the re-entry of a de-orbiting satellite. They used this data from different observers to triangulate and document the re-entry process. Other amateur observers have web-sites that you can join, and submit your findings of fallen meteors in order to give more accurate predictions in the future for meteor per/hour peaks. They make available free software that you can use with your computer to ease the process; and make it more interesting as I like!

The following pages will explain the basics and what you need to setup your lab. If this is something that interests you, visit my website at http://phoxes.comhttp://phoxes.com to learn more. You will also find free software and tools to find the necessary stations to tune into throughout the USA.

Step 1 Safety Time - Warning

Installation of antennas near power lines is dangerous. For your safety, follow the installation instructions that comes with your antenna. Each year, hundreds of people are either killed, mutilated, or they receive severe, permanent injuries while attempting to install or remove an antenna. In many of these cases, the victim was aware of the danger of electrocution but did not take adequate steps to avoid the hazard. For your safety, and for proper installation, please read and follow the safety precautions that accompany your specific model of antenna.

If you are installing an antenna for the first time, please, for your safety, as well as others, obtain the assistance of a professional installer or electrician. He can explain which mounting method is best suited for the size and type of antenna you are about to install and help you obtain on-site assistance.

Remember, the antenna, the mast, the cable and any metal guy wires are excellent conductors of electrical current. If you are touching the antenna, the mast, or any of their components and they come in contact with an electrical wire -- even the slightest touch -- an electrical path will be completed through the antenna and the installer -- THAT'S YOU! If you are unsure about how to install your antenna, or you have any doubts about your abilities to successfully perform the job, stop and obtain the help of a professional installer.

If any part of the antenna system should ever come into contact with a power line, DON'T TOUCH IT! NEVER TRY TO REMOVE IT YOURSELF! CALL YOUR LOCAL POWER COMPANY. They will remove it safely.

Comments

[static]

I think it would be interesting to have a FM receiver that could sweep the FM band an use an omni- directional antenna. That should let one observe multiple meteors over a given time period during a shower. Sure that will take some training of your ear ignore the stronger normaly received stations.

[kouker]

Great Instructable!

[GorillazMiko]

Great Instructable. Very interesting as well (as thearchitect said). Awesome job.

[thearchitect]

This is very interesting. Do you have any sample sound files? I checked out your website, very rich and lots of fun. Thanks for posting!.. Cheers, K.

[foxmcf]

No - I don't have any sound clips, but you can visit the JAS site for some samples. Thanks for the comments.