Transponder and radar

Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
Hi, I am an amateur drone flyer, and electronics enthusiast with engineering background. Along with some other friends we have the problem that our drones sometimes fly out of sight range, and if it happens that they fall to the ground, is extremely difficult if not impossible to find them for recovery, since we don’t have a way to track them through low vegetation. This is important to us because of the value of the components that might survive the fall.

I have read something about RF and 433MHz thinking it could serve the objective of a tracking device, therefore I need advice or ideas on the best ways to build a beacon to place it on the drone (as a transponder) and a receiver (as a radar) to track the thing down. I know is not going to be easy and I am not fixed to the idea of using 433, so if anyone can suggest where to start or an easier solution I will be in debt. Lastly if you rather to write me (technical articles or useful references) please do it to: <snip> .Thank you in advance.

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Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
Thanks Kermit2 for the fast reply. I was looking for it yesterday, however at the famous commerce company who starts with "Am..." the customers doesn't seem to be very happy with it. I've seen some other similar references with same results, then I thought "why buying something that might be defective, if I can try to make one and hopefully make it better" (I told you I am an enthusiast). Of course I will have to get quality parts somewhere but that is how one of my sons and I built our drone, it makes me very happy to be able to show him that effort most of the time leads to good results and that knowledge is the only asset that nobody can take away from you.
 

Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
OK. This must be difficult to achieve or everybody is too busy. Planning to move on in a different direction .... How about triggering a buzzer remotely? Then I ring on a transmitter and the drone cries back letting me know where he is. Anyone?
 

crutschow

Joined Mar 14, 2008
34,285
OK. This must be difficult to achieve or everybody is too busy. Planning to move on in a different direction .... How about triggering a buzzer remotely? Then I ring on a transmitter and the drone cries back letting me know where he is. Anyone?
That sounds feasible, if the receiver and buzzer are not too heavy.
You might be able to find an appropriate remote control device on ebay.

Alternately is there a control function on the drone that could do double duty as the buzzer control?
That way you wouldn't need a separate transmitter/receiver.
 

Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
That's a great idea Crutschow I guess you nailed it. My current transmitter have channels to spare, and a simple circuit connected to the receiver might do the trick, before passing through the flight controller. Thanks buddy.

Please tell me something else just because I became curious on it, Was the idea of the transponder and radar so hard that everyone skipped to make comments? What is the real big deal, Interference with TV signal? Complexity to set the antenna? In this RF forum many people should be familiar to the topic and being able to lead me. I guess you'll agree that applications for it are so vast that everyone might have it solved, at least with one or two designs.
 

camerart

Joined Feb 25, 2013
3,724
Hi R,

What I suggest is to add a GPS to your drone, along with a 433 radio module. For the GPS check Ublox, as they make a range of them. Some of the later models are smal and light. I use NEO-6 and LEAH-6.

For the radio check the RFM range by Hopefm or the very similar Semtech chps. I have Semtech SX1276.

The GPS and radio chip need to be controlled by a controller chip. I use PIC 18F2431 and 18F4520, but I think I would check Atmega 328 or similar and perhaps Arduino.

What happens is: The GPS sends it's location at all times, and keeps transmitting if you crash. Here is a link to a Relay, that if held high (Up a tree or model or similar) will relay to your BASE radio chip/control/LCD the whereabouts of your model.

I am working on something similar, but I am an amateur compared to Stuart Robinson. Here is a link to his Relay:.http://www.loratracker.uk/?p=312 Have a look at the other sections of his pages, where you will find many things to interest you.

Good luck.
Camerart.
 
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Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
Hi R,

What I suggest is to add a GPS to your drone, along with a 433 radio module. For the GPS check Ublox, as they make a range of them. Some of the later models are smal and light. I use NEO-6 and LEAH-6.

For the radio check the RFM range by Hopefm or the very similar Semtech chps. I have Semtech SX1276.

The GPS and radio chip18F2431 need to be controlled by a controller chip. I use PIC 18F2431 and 18F4520, but I think I would check Atmega 328 or similar and perhaps Arduino.

What happens is: The GPS sends it's location at all times, and keeps transmitting if you crash. Here is a link to a Relay, that if held high (Up a tree or model or similar) wil relay to your BASE radio chip/control/LCD the whereabouts of your model.

I am working on something similar, but I am an amateur compared to Stuart Robinson. Here is a link to his Relay:.http://www.loratracker.uk/?p=312 Have a look at the other sections of his pages, where you will find many things to interest you.

Good luck.
Camerart.
Hi Camerart. Thank you very much for making time for me. I am glad that you are also promoting the previous idea and provided me bunches of good references. Happens that I am familiar to Arduino but for RF probably need to get me the whole "for Dummies" series, but seriously really wanting to learn so thanks again.
 

camerart

Joined Feb 25, 2013
3,724
Hi Camerart. Thank you very much for making time for me. I am glad that you are also promoting the previous idea and provided me bunches of good references. Happens that I am familiar to Arduino but for RF probably need to get me the whole "for Dummies" series, but seriously really wanting to learn so thanks again.
Hi R,
For the radio modules, go for the higher numbers RFM96 or SX1276. Compare the Data sheets, as they are very similar, for which is easier to read.
To set-up the radio chip using a control chip, I think this is what happens: The radio chips load the default registers, at power on. The control chip then puts the radio to sleep, and loads the changes to the registers, to suit legal or preference register settings, overwriting the default values. As easy as that:) I haven't succeeded yet:(
C.
 

Thread Starter

Ramiro A. Suarez

Joined Nov 15, 2016
7
Great addition, unfortunately not so familiar with registers, I just use it at IDE level and acknowledging the importance of managing and understanding the interrupts. How long have you been trying so far?
 
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