FM Radio Location Device?

[Lupich]

Does anyone mass-produce or make an affordable FM radio location device?

I'm sticking with LPR for now but that doesn't mean I won't try and push my limits once in a while and some of my 2-stage rockets simply disappear and we get only a rough estimate of the landing area.

I heard before that someone could simply make a small FM beacon that uses little power (The more power, the more range, etc) so it can be small and the concept it that is basically sends out either a beep, or a constant tone of some sort and you wander around the approximate area with a cheap FM radio until the tone gets clearer to put you in the right direction.

I think that an FM location device coupled with an audible signal of some sort would be far cheaper than anything like GPS and the like.

I would intend to use the FM, and audio trackers coupled with RockSim to see if I can approximate my landing area and see if I can keep a great recovery rate going. :o

Is anyone familiar with something like this?

[bigredbee]

Not sure what you mean by "affordable", but I offer FM beacons starting at just $59.00. An amateur radio license is required, they're just $14 for ten years, plus the cost of studying for your test.

This, along with a receiver starting at $80 to $150 and a home made antenna, and you're all set!

There are also some "fm transmitter kits" that you can get from places like ramsey and other places, but they are pretty low power and have a limited range.

And, of course, you can also roll your own!

-- Greg TRA 7960 K7RKT

[Lupich]

Not sure what you mean by "affordable", but I offer FM beacons starting at just $59.00. An amateur radio license is required, they're just $14 for ten years, plus the cost of studying for your test.

This, along with a receiver starting at $80 to $150 and a home made antenna, and you're all set!

There are also some "fm transmitter kits" that you can get from places like ramsey and other places, but they are pretty low power and have a limited range.

And, of course, you can also roll your own!

-- Greg TRA 7960 K7RKT

Very interesting... Do you have any more details on the license process (I will Google, but like first-hand info!) as well as some more information about the electronics you sell? I very interested in buying a system like this in the future.

EDIT: Nevermind! Saw you're signature. :)

[sylvie369]

I use Greg's beacon (the BigRedBee transmitter), and in fact I earned my license for the purpose of being able to use it. It works great, and yes, I have flown it in LPR rockets. It's quite a bit less expensive than the other systems I see people using, and other than the very minor inconvenience of having to have a license, I don't see any downsides. The license requires a little studying and self-testing, and then one simple short test - no problem.

Are you in the United States? That makes a difference, of course.

[WillMarchant]

If you are in the USA then you might want to check this page http://www.arrl.org/getting-licensed to learn more about getting licensed.

[Lupich]

No, I'm in Canada, BC... I'll need to find out.

[WillMarchant]

http://www.rac.ca/en/amateur-radio/beginner-info/

[n5wd]

No, I'm in Canada, BC... I'll need to find out.

The Radio Amateurs of Canada (http://www.rac.ca/) is the national organization of hams in Canada. I'd start there to find a licensing course in BC. (http://www.rac.ca/en/amateur-radio/regulatory/courses/)

Back to your original question: yes, while it's possible to use the FM broadcasting band and a low-powered beacon that operates within that band, the obstacles are many for success.
(1) there are very few if any commercial radios made that tune the broadcast band on a portable receiver that takes an input from a directional antenna (which would be required) that are not part of an amateur radio handie-talkie. That means you'd be stuck with the lower power of a license free broadcaster and no real easy way to hear it.
(2) that directional antenna- yes, you can purchase commercially made yagis for the FM band, but they're made for clamping onto a roof or a tower - they're usually fairly large and long (5-7 elements) and are often matched for a 300 ohm twin-lead output - you'd need to provide a conversion to 50 ohm coaxial input into the radio.
(3) your antenna is going to be more than twice as big (from one tip of the elements to the other) and mine (built for a 435MHz satellite transmitter) is pretty unwieldy in the bush, already. You'll have even more problems swinging that honkin' big antenna around.
(4) finally, there's the problem of the primary user of the band - FM broadcast stations. You have to find a frequency that is unused so that no signal can be heard (even very weakly) at the highest altitude that YOU will be trying to receiver your beacon. The problem is if you climb a hill, and now there's a very weak FM station 100 miles away that your receiver can hear, and it's signal is even close to being the same strength as your beacon, the FM receiver's "capture effect" will make your beacon unusable. You just absolutely have to have a clear frequency on channel that you're trying to use.

So, while it can be done, it's certainly not as easy as using one of the Bee beacons (my choice of beacons, as well).

73 Wayne N5WD