I have an idea, all of it is perfectly possible however I need to be able to get my hands on a tracker ... a small tracker. Not incredibly tiny but 7.5mm³ is the biggest it can be. Range does not matter too much other than it has to be more than 15 meters or so.

If that isn't possible then whats the smallest size possible whilst maintaining 10 meters range?

 

Here's a simple tracking transmitter circuit:

 

colin, did you perhaps read the posters question? It needs to be 7.5mm^2
Owen, for that size you really don't have any practical options. It could be done with the smallest of surface mount chips but it'd still be slightly larger than that and the battery life would be abominable.

For what practical reason would you want to do something like that? If something is within that distance you can usually see it. You'd be better off with something like a simple acoustical chirping device.

__________________

 

Yes. I did read the posters requirements. I am also a Physics teacher. He did not say anything about the height. It can be 30cm high. That's why the circuit I posted is ideal.

 

Well this is the reason (little odd, just an enquiry to see if it could be done): tranquilising darts. My idea was you could shoot something in the wild, the dosage is not strong enough to immediately prevent much movement as the point is for it not to be lethal, the hunter then tracks the animal as best s/her can. However depending on the animal a short range tracker could be useful (it going into a den, hiding in a thick hedgerow, etc). But often animals will knock the darts out or they will fall off quickly, but if the dart is made out of two parts: tracker and needle, liquid and feathers, then the latter part could be dislodged easily but a small tracker and the needle being mostly in the animal the former part might not be.

I know, I know. Lame idea, but I thought it wouldn't hurt to find out if such a thing was possible (the tracker, the rest of the concept would be possible if the weight distribution was acceptable).

And sorry, I meant 7.5mm³, sorry for the mistake.

 

That's what this circuit has been designed for. It is fabricated with SM parts and uses two tiny button cells. It produces a beep-beep-beep to make it easy to detect.

 

Get rid of the 170cm antenna and what kind of range does it give you?

Not much.

__________________

I do not answer private messages asking for help because no one else can: benefit from advice I may give or correct me if I'm wrong.

Please ask on the open forum if you have a question and I'll be happy to help, if I know the answer.

 

A few feet if you're lucky. And you'd need a 6 foot antenna to home in on the tracker, not exactly user friendly. I thought we'd already gone over this with this circuit in another post colin, it's not a tracking transmitter, it's a simple beacon. Also I'm not sure if I mis-read it at first or if it's cause that damn little superset is so small but apparently its 7.5mm's cubed.
It's not a bad idea Owen, but not very practical to home brew something in that limited of a space.

__________________

 

Alright, maybe in a few years, eh?

But any other signaling things that could be that size (accuracy within a few meters?) that would last up to five minutes or so?

 

THey use tracking string for that kind of thing...for all intents and purposes it lasts forever. and has a much larger range than 10m.

Spool-
http://www.turkeyhuntingsecrets.com/...er-30spool.htm
Case-
http://www.turkeyhuntingsecrets.com/...acker-2500.htm

But, more in line with what you seek: an "electronic tracking wire" (basically an RF transmitter in the arrowhead instead of a wire)
http://www.turkeyhuntingsecrets.com/...ter-system.htm
http://www.turkeyhuntingsecrets.com/...ransmitter.htm

Also, perhaps active RFID might be a possibility (not passive).

__________________
Tanaka Sensei (avatar) says: Please spell it "ridiculous" correctly! Not "rediculous". ^^

 

The only thing I can think of is a piezo speaker to make an audible chirp, but the output from anything that small isn't going to be loud enough, and if the animal fell on it when it went down you'd get nothing.

__________________

 

ROFL. Tie a piece of string to it =O Genius! => At the very least even if it comes out afterwards you'll have an idea of where the animal's general path went.

__________________

 

Haha, Sceadwian, I think you're thinking of a harpoon...

And dknguyen those arrowheads look like they could inflict a lot of damage (tranquilisers are by far most effective when injected into a rear leg - lots of muscle) if we're going along the lines of it being non lethal ... plus it appears it is meant to be propelled via a bow.

However, rifles have been known to be able to fire darts of varying descriptions. It could be possible with a high powered rifle, a long shaft to hold both the transmitter and the tranquilising fluid, a short needle protruding from a smaller arrowhead... and it may be possible at relatively short range fired...

 

We already sell hundreds of these transmitters for use as a capsule inside a hollow arrow.

 

Oh? Links? Descriptions?