I (a newb) would like to design a small & simple GPS tracking system for my 2 cats

[hedgehog90]

I (a newb) would like to design a small & simple GPS tracking system for my 2 cats

Hi.

First let me tell you about myself. Just at the mere sight of the first line you can probably tell already that I am not an electronics expert by any stretch of the imagination, I am a newb.
However - I did receive an A in my Electronics A Levels, but that is not a valid indicator of my true knowledge of electronics.
Ironically, I don't understand some of the most basic things. Grounding. What diodes really do. AC / DC (although I am aware of the famous rock group of the same name)
For my electronics A level coursework I designed a scrolling sign made up of 6 or so starburst LED displays. I programmed a chip to say something like "I LIKE ELECTRONICS". Completed in a day. Got me an A.

**broken link removed**

Also, my professional job is as a game designer. I write lots of code, and I have a very good understand of all things code-like.

Now, here is the problem that I want to solve:

We have 2 cats, Tig and Ollie. We live in quite a nice rural area, but unfortunately, we've lost 2 cats to the road and the lane near us.
It causes us a great deal of stress just letting Tig and Ollie out for 2 hours every day. So, we bought a loc8tor and several tags to track them. It's a simple device. the tags emit a pulse, the loc8tor shows you the signal strength from 0-100. It claims to work with tags up to 600 feet away (with no obstructions it's more like 400 feet, but you expect it)
I've looked inside the tags and the handheld loc8tor, and it looks pretty simple. Certainly not worth the £80 we paid for it.

Here's some stuff to read:
**broken link removed**
**broken link removed**

Anyway, for the past few days, we've been finding Tig alarmingly close to the road, and while he spooks at the sight of an unrecognised visitor in the house, he looks pretty mellow while cars and massive lorries race past him at 60 mph...
Because the road is so far away, we can't get a signal of him without running around the garden and the nearest field for quarter of an hour. It's a pain.

Before we bought the overpriced loc8tor, we looked around for something similar but with GPS instead of RF.
Such devices exist, but they were enormous... I found a lot of pictures online of very perturbed cats with heavy weights wrapped around their neck. Also, the GPS tracking came with a monthly charge...

So today I looked around online for info on GPS chips. I have an android phone with GPS, how big can they be I wondered. Well, they're tiny.
Finally I got round to thinking that maybe I could build some sort of cat tracking device myself with minimal cost?
I like opening stuff up and having a poke around. I fixed (and then broke) a PS3 by taking it apart. I'm quite good with my hands.

I understand this might sound like a naive, over-confident thing for such a electro-newb to say, but ideally, I want to create a deice, no bigger than a loc8tor tag (30.5mm x 19.5mm x 8.5mm) that will regularly inform me of it's exact position on the globe (ie - in the field next door most likely) via my phone or computer.

Now, I had a bit of a think and realised there's a problem here, apart from the task itself.
Your normal GPS (the GPS in the car, the GPS in your phone) works like so (I'm assuming):
GPS requests position -> Satellite receives request, calculates, sends response to GPS -> GPS receives response and displays.
But for my supposed device it would be:
GPS requests position -> Satellite receives request, calculates, sends response to my phone's GPS -> Phone receives response and displays.

Also, can you just buy the core mechanics of a GPS and have it request and receive with just any satellite? I expect there are permissions and restrictions that need to be gotten past.

As I'm writing this I'm realising more and more that what I want seems like I will unlikely be able to make such a thing on my own... But having said that, in the last couple weeks I was called upon to design a call management system for a friend who runs a small call centre, and as difficult as it was, I was able to do it.
The same is true when I started making games. It looked incredibly difficult and I felt it was impossible, but it didn't take long for me to get a grasp of it all.

If I put my mind to it and do the research, I feel like I should be able to do this as long as I have the necessary tool and help.

So, to clarify, I would like to design 2 small tags, likely running off 2 small 1.5V batteries, that will get it's position via GPS and send it to my phone/computer, with the ability to be switched on and off. Sealed withing a plastic container that I can then attach to my cats' collar.
Is this feasible?
If so, I would like very clear instructions on how to do so.

I apologise for the length of the thread and the amount of unnecessary info.

 

[sky_123]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Glad you're trying to solve this problem, and you're right, that loc8r device does seem a rather expensive solution.
Just to throw some ideas out there, what if there was a device that you could pre-program an outline of the area that
the cat is "allowed" to reach (i.e. before it reaches a road, and before it exceeds a certain range), and then the transmitter
sent a signal warning you that the cat had reached the area - with (say) one of 4 tones (or indicator lights), to indicate the
side of the area that the cat has reached, so that you can run in that direction.
All that would be based on computations based on the GPS location of the cat. So the tag would be a GPS receiver,
some computation device (microcontroller) and a transmitter that only switches on when the range was reached.
It may be cheaper, and easier to implement. Not saying it's the best idea, but I suppose you need to weigh features vs.
cost and size and so on, to come up with the best-compromise design.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

I posted the same thread on electronicspoint.com and I was told that GPS is one way, there is no request and no response, the gps device just detects several satellite signals, trianglutes and determines a position.
This makes a lot of sense now...
So, there is no easy way of sending data from my cat to my phone/computer, because that requires a very strong transmitter, which isn't realistic.

The way other devices do this, is by sending updates via SMS, through mobile networks... so not only do you need a good satellite signal, you need good mobile reception too.
I think I've quickly come to the conclusion that GPS is not feasible.

So now I'm wondering if there is a way of making a better loc8tor.
I've been looking up how the loc8tor works, what sort of frequencies it operates at, and I read on this site that the handset and the tags operate at 2.45 GHz, which seems incredibly high to me (source - https://www.rfidjournal.com/article/view/3012/1)

What do you think of this more realistic option then? How would I go about either increasing the range of this device or making my own stronger handset/tags?
If they're behind the shed I realise it's not going to make things much better, but if it would make it easier to find them from the second floor of our house when they were in field/near the road then that would be great.

Although I guess if you made the signal too strong it would make finding them directionally less accurate...

Oh well.

My other thread if you're interested: https://www.electronicspoint.com/ne...ing-system-my-2-cats-t251774.html#post1489589

 

[sky_123]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

A GPS module is a (highly complex) radio receiver (not transmitter), available at low cost.
It can continuously (well, every second or so) provide an indication of where the cat is,
based on satellite transmissions.
A microcontroller could compare the co-ordinates from the GPS module, with a pre-defined boundary.
If the cat exceeds the boundary, you need to get that information to the house.
That could be done with a radio transmitter module. A few hundred meters should be
feasible with low power. However, to conserve power, you only want to transmit when
the cat approaches/exceeds the boundary. The transmitter could send a simple code
that indicates that the microcontroller has determined that boundary A,B,C or D has
been exceeded.
There are pre-made 2.4GHz modules (known as zigbee modules) that work as transmitters or
receivers. I don't know what the range is, but it's not far.
Since you want this to be legal, you're restricted to certain frequency bands and certain
transmit power. You can meet the legal requirements by using a pre-made transmitter
module designed for the band you choose. I think certain bands in the region of 400MHz, 800MHz
are also available in the UK (I'm not an expert on these bands and the transmit power you're
allowed on them).

Just to show you they type of stuff available (not suggesting these are exactly what you want or not),
see **broken link removed**and the **broken link removed**.
For £3.99 that gets you a transmitter with what they claim is 300m range in the best conditions, and
about 20mA current consumption.
£11 gets you a GPS module, see **broken link removed** that is 11mmx11mm in size.
Note that this one doesn't include an antenna, so you need to factor that into the cost. It consumes 40mA however,
but a small LiPo rechargeable battery could possibly power it for the day.
You already seem familiar with microcontrollers to tie it all together.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Ok, I've had an idea.

So, the problem is, my locating device and tags are not strong enough and not accurate enough.
Our house is situated between 2 fields. There are many trees in the hedgerows.
I would need to buy/build several radio transmitter/receivers, which I can attach to the cat's collar and to trees surrounding the fields (the higher the better).
Each transmitter/receiver will need to detect signals from either cat and from neighbouring transmitter/receivers.
And, here's another clever idea - I have an FM receiver on my Android phone. So, I could program an app to detect incoming signals from the nodes, and based on number of signals, their locations and the signal strength, I can estimate on my little app their position on a map, and using my phone's gps, I can also see where I am.
When I get close enough to the cat to receive their tag's signal on my phone (again - if that is possible to use the phone's firmware-based FM receiver for such a task), then I can use the strength of the signal and my own location (using the phone's GPS) to work out more accurately where the pesky blighters are.
If the cat's are not detected by the receivers, then give me an alert on my phone.
I don't need gps for the cat's collar for this, but I guess it could be added to make it even more helpful.

...

How would I do any of this? I HAVEN'T THE FOGGIEST!
I have some experience in programming microcontrollers, and I have tried my hand at android apps before, but if you gave me all the ingredients for this, I'll still be left scratching my head.

It would require building a set of programmable receiver/transmitters, connected to replaceable power sources (with some luck though they should last a while, considering my cat's loc8tor tags last months on just 2 tiny 1.5V batteries), programming them so that they send out a signal with the cat's location and signal strength, and then using that data via my phone's FM receiver and my phone's GPS, display the presumed radius of the cat's possible location on an aerial map, along with my exact position.

Could someone please tell me if this is a feasible idea, and if so, please tell me what components and tools I'd require, and finally how I would build one of these receiver/transmitter things.

**broken link removed**

Edit: Hmm, after a little research I doubt I will be able to use my phone as a radio receiver. While it can pick up a range of FM signals, it probably won't pick up the frequency I'm hoping to broadcast

 

[sky_123]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

It's a tough one. If you make it too complicated, there is a lot to go wrong, and the cost shoots up too.
But I like the idea of tree nodes. It means the cat transmitter can be very low power.
Lets say you have just a few locations that can cover the approaches to most dangerous areas (i.e. roads).
Maybe something like this is an idea.

The cat electronics is a low power transmitter, that transmits once every couple of seconds or so, at a low power
that can only be picked up from nearby.
If a tree receiver picks up the transmission, then it sends a much stronger transmission that can reach your home.
If the tree receiver (say) consumed 20mA, then the tree battery charge might last a couple of days (or make it a larger battery
for weekly replacement). It could transmit on a frequency just outside the FM band, which might be ok if the transmit
signal level is low. Each tree node could transmit a different tone, so you know which direction the cat went.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

If the tree receiver (say) consumed 20mA, then the tree battery charge might last a couple of days (or make it a larger battery
for weekly replacement)

Really? 1 week max? The locator tags last months with just 2 small 1.5V batteries, and they claim to have a range of 183 metres / 600 feet! I mean, it's absolute bollocks - they range about 100 metres in an open field, if that. Also, whenever we try to find them they flash and beep. The power consumption is something quite extraordinary, I can't believe they last as long as they do with just 2 AG10 alkaline batteries.

The idea is that the Tree nodes transmit their neighbour's signal, so in other words, each node acts as a signal booster. In theory, if i set up 10 nodes from left to right separated by 100m each, then the signal will eventually reach the right node by being retransmitted by each node before it, covering a total distance of 1km.

I'm now thinking actually, that I could keep the loc8tor tags as they are, and have the nodes pick up the loc8tor tag signal, and then transmit the data to the other nodes with a slightly stronger signal... but that would require 2 receivers on different frequencies...
So if that's not possible, then I guess I could have them all operate on the loc8tor tag's level of 2.4ghz and space them accordingly.
I don't think I can make anything smaller than the locator tag, so I think I might have to stick with them for the cats. Any bigger and it would be unkind.

Also, I found this:
https://android.serverbox.ch/?p=549
So there is some hope with the android acting as the main receiver/display unit.

 

[betwixt]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

If Tiggy and Ollie are like most cats, the solution is far simpler. Work out how long it takes them to reach the road then at that interval, play back a recording of a cat food box being shaken. Used to work here but failed when the cat went deaf!

Brian.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

My cats are not like most cats. They're weird.
They react to cars like... well, like they're not real. They are completely un-phased by revving engines and whooshes from the nearby road. Yet they are terrified of my nan.
They don't react to their names being called, despite doing this since we adopted them. They don't react to treats being shaken unless they are starving.

I don't want to spoil their enjoyment of the outdoors, I just want to be notified when they do go a little astray.
I think my project outline is quite efficient in doing that, and I don't believe it would cost that much to implement.

For now, just imagine I want to build one of these receiver/transmitters. How would I go about doing it?

Also, found this:
Loc8tor deisgn patent -http://www.faqs.org/patents/app/20110012775

 

[sky_123]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

I think maybe it's best to get the basics of the scheme, i.e. a cheap receiver and a cheap transmitter module (e.g. Maplin or ebay etc) and a couple of small microcontroller boards and try to write some algorithm (e.g. transmit a code burst every few seconds, and try to receive it and light an LED when it does). That way you can experiment to see the current consumption (with a multimeter) and also gain confidence if you did want a multi-node type arrangement (which personally I think could grow into some complicated scheme : (. Anyway, by assembling the Rx and Tx modules, you'll gain enough knowledge/confidence to then expand the arrangement if needed.
Some example info on getting started with microcontrollers is attached if you need it (just google for an AVR or PIC board, and get a free C compiler for it). It doesn't matter which one you choose, just get something that is easy to program (e.g. via on-board serial or USB) and many C compiler vendors offer compiled-code-size restricted (e.g. 2 or 4kbyte) or time restricted versions of their compilers for free. You can write huge programs in 2 or 4kb because you won't be linking many libraries, so it's actually quite hard to exceed the few kb restriction.

 

[godfreyl]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

An alternative may be to have a device on the cat that shouts at it when it gets too close to the road. That way you don't know where the cat is, but it's discouraged from going to the road.

For that, you'd need a receiver on the cat and a row of small transmitters between the house and the road, or perhaps one transmitter with a very long wire antenna forming a "don't pass" line in front of the road.

I guess the noise emitted by the cat collar should start soft and get louder as it gets closer to the road. It it suddenly makes a loud noise, the cat won't know which way to run.

 

[betwixt]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Firstly, GPS is not the way to go. For one thing, it relies on a good signal from several satellites and cats being what they are, the signal wont be seen while they are under bushes, fences, cars etc. If GPS was used, you still have to radio the signal back to 'base' and decide whether it is within the allowed boundary or not. GPS and a transmitter will eat quite a lot of battery power so you would need to periodically recharge or replace them. A rechargeable cat would be an interesting animal though!

Do you really need the location to be known other than proximity to the road? There is a fairly simple method of detecting the proximity of a transmitter to an antenna as long as the antenna can be placed along the boundary so next questions are: How far away from the road are you and is it feasible to run a single wire from base to the road and then along the length or road you want to monitor?

Brian.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

For now, let's make this simple:
Lets suppose I want to make a tag for 1 of my cats consisting of a transmitter (and possibly a receiver too, to tell the transmitter when to start transmitting which would be much more efficient), and a receiver attached to an arduino attached to my phone, RF at 433MHz with a range of 300m. And consider that the cat's tag is operating off 2 LR44 1.5V batteries.

Can I make anything small enough that will send a dumb signal to my arduino-receiver-phone thing?
The cat's transmitter only need to broadcast their ID, Ollie or Tiggy.

The receiver attached to my phone should pick up the signal when within 300m, and then it needs to very basically decode the signal for the ID and get the signal strength.

I understand that this won't be directional like the Loc8tor, but with atleast 3 nodes it will be quite accurate in telling me their position.

Anyway, for now, let's just imagine that this is all I want to do. 1 transmitter, 1 receiver.
What would I need to build this, and how would I build this. Please be detailed.

I appreciate all the other suggestions and all of your help, but I really just want to know how I would do this exactly. It can be improved upon later.
Thanks.

 

[rohitkhanna]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Haven;t read ALL of your posts, but i got the flavour.
Use a GPS module dude. Goggle it. GPS can manage 10-20 ft accuracy, which I think is OK for your needs. And its in open space -- even better !!
Add some sort of RF transmit/receive... maybe a GSM bit to it if you like. Though in YOUR case a more basic Rf tx/rx would prolly be simpler & better.
Have the Rx piece at home, where you connect it up to something which KNOWS whats ok and whats out of bounds. Signals an alarm maybe if out-of-bounds is detected.

I strongly suggest that you do NOT use just 'signal strength' to figure it out. Toooooo many variables involved there..

That sounds to me like the best solution, and i get the feel you can figure out how to do the rest.

cheers!

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

I've ordered some basic stuff from ebay:
Some pcb stripboards
A better soldering iron
5 x PIC12F683-I/P
PIC Programmer

I haven't got an arduino and I haven't bought any components (apart from the PICs), because at this point that would be silly.

I've been looking around for tranceivers, and I would guess that the TRM-433-LT will do the job best. It's very small, efficient and apparently easy to operate. It boasts and incredible range, almost 1km.
https://www.linxtechnologies.com/en/products/modules/lt-rf-transceiver

If that's no lie, I'd be interested in getting a GPS to work with it.
That way, I only need 3 transceivers (2 for each cat, 1 for me), 2 GPS modules & 1 arduino. Relatively simple.

All I need is some more advice and a helpful hand to take me through the process of putting it together.
I will be chuffed to bits if I can make something better than the Loc8tor

 

[rohitkhanna]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

For now, let's make this simple:
Lets suppose I want to make a tag for 1 of my cats consisting of a transmitter (and possibly a receiver too, to tell the transmitter when to start transmitting which would be much more efficient), and a receiver attached to an arduino attached to my phone, RF at 433MHz with a range of 300m. And consider that the cat's tag is operating off 2 LR44 1.5V batteries.

Can I make anything small enough that will send a dumb signal to my arduino-receiver-phone thing?
The cat's transmitter only need to broadcast their ID, Ollie or Tiggy.

The receiver attached to my phone should pick up the signal when within 300m, and then it needs to very basically decode the signal for the ID and get the signal strength.

I understand that this won't be directional like the Loc8tor, but with atleast 3 nodes it will be quite accurate in telling me their position.

Anyway, for now, let's just imagine that this is all I want to do. 1 transmitter, 1 receiver.
What would I need to build this, and how would I build this. Please be detailed.

I appreciate all the other suggestions and all of your help, but I really just want to know how I would do this exactly. It can be improved upon later.
Thanks.

Power source is ALWAYS a concern for such projects. I admit I haven't looked into the power requirements, but here's some general thoughts --

* power-up only when needed, not all the time. Not so easy with GPS, since it takes a while to 'acquire' the satellites. Also I admit I haven't looked into how much juice GPS + 433Mhz Tx will consume. At least the Tx can be operated in burst mode only every N seconds/ minutes.

* look into using CR2032 rather than the little LR44 jobs. Much higher capability. Also maybe LiPo batteries - thats MAJOR crunch for the size, with a few precautions.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Power source is ALWAYS a concern for such projects. I admit I haven't looked into the power requirements, but here's some general thoughts --
* power-up only when needed, not all the time. Not so easy with GPS, since it takes a while to 'acquire' the satellites. Also I admit I haven't looked into how much juice GPS + 433Mhz Tx will consume. At least the Tx can be operated in burst mode only every N seconds/ minutes.

I figured this - turn on the gps ONLY when I ask for the tag's location. And only transmit when I ask it to. Therefore, the only thing it will be doing most of the time is checking the receiver.
I could also have an on/off state so that when they're not outside I can turn it off.

Oh yes, I've just remembered. I would like to implement a small speaker into the tag as well.
The loc8tor has red light that flashes when the tag is being located. it also beeps. I don't need the red light because they're never allowed out at night, but the beep is very helpful when in close proximity and they're hiding in a hedge or something.
However, the first thing that bothered me about the loc8tor was that you can't tell the beep/light to turn off. So ideally, if I were to implement a small speaker that beeped intermittently, I want to send a signal to the tag saying, "start beeping" and when it's not needed, "stop beeping"
So that's something to think about - a small low energy beeper. Any suggestions?

Also... I've been googling this for ages and because I don't know very much I'm struggling to find an answer:
I want to find a very small PIC microcontroller, but not so small that I can't use a regular soldering iron. But just right. The goldilocks PIC.
I looked inside one of the Loc8tor tag and I could just about make out the writing on the microcontroller. It is a PIC16F636. Very Tiny. Too tiny in fact.
So, I Googled small microcontrollers and found this:
**broken link removed**
I think the size of the one on the right is necessary for the tags. Correct? Now, what do I google if I want a decent 6/8 pin PIC microcontroller that will do the job for me?
The basic chunky 8 pin PICs I ordered are just too big, so I cancelled them before dispatch.

Also, some related questions:
Firstly, what do you call a small microcontroller?.... (this is not the feedline of a joke I've just thought of, I genuinely want to know if there is such a name for these special micro-microcontrollers)
Secondly, How do you program one of these tiny microcontrollers? I imagine you need an adapter of some sort with a normal microcontroller programmer.
Thirdly, Why don't vendors show the size of the PIC they're selling? I look at the specifications everywhere and they never show the dimensions!!! Why is that?

 

[rohitkhanna]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

I've been googling this for ages and because I don't know very much I'm struggling to find an answer:
I want to find a very small PIC microcontroller, but not so small that I can't use a regular soldering iron. But just right. The goldilocks PIC.
I looked inside one of the Loc8tor tag and I could just about make out the writing on the microcontroller. It is a PIC16F636. Very Tiny. Too tiny in fact.
So, I Googled small microcontrollers and found this:
**broken link removed**
I think the size of the one on the right is necessary for the tags. Correct?
The basic chunky 8 pin PICs I ordered are just too big, so I cancelled them before dispatch.

Also, some questions:
Firstly, what do you call a small microcontroller?.... (this is not the feedline of a joke I've just thought of, I genuinely want to know if there is such a name for these special micro-microcontrollers)
Secondly, How do you program one of these tiny microcontrollers? I imagine you need an adapter of some sort with a normal microcontroller programmer.
Thirdly, Why don't vendors show the size of the PIC they're selling? I look at the specifications everywhere and they never show the dimensions!!! Why is that?

LoL !! n1 ... "goldilocks PIC"
Yeah... maybe the small micro-controllers need to be renamed nano or pico now.

In my experience ALL manufacturers show the size of their chips. However.. they use techie terms like TSSOP, TQFP, PDIP, MLCC, blah blah. You need to be able to understand what each means, and what sizes it implies. Checkout SMD/ SMT packages on Google/ Wikipedia to start with. And oh yeah.. i do hope you know about Digikey. Thats one amazing source for all of this stuff.... prices/ info/ specs whatever !

I have found that the smallest (haven't tried smaller as yet) one can do at 'home' is the TQFP size. But you need a small/ sharp iron, thin or paste solder and some good magnification while doing it. Checkout websites on soldering SMD packages... some good tips are on the 'net. Oh yeah... also a steady hand. So don't smoke anything before you solder !!

About the programming - you need to build in the interface on your final board to program it. Atmel AVR's use a 6-pin i/f (SPI), reduceable to 4 pins + GND connection. PICS i'm not sure about ... maybe same maybe even less.

 

[betwixt]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

PICs are programmed via a three wire interface, a clock, data and programming voltage (VPP), there are lots of very simple programmers on the Internet although I would strongly recommend a PICKit2 or 3 from Microchip or one of the 'ebay' Chinese clones.

Work out exactly how many pins you need then go for the smallest PIC that will do the job. They are all available in diferent pinned and SMD packages, from experience, SSOP packages are easy to solder, the others are a bit tricky.

Brian.

 

[hedgehog90]

Re: I (a newb) would like to design a small & simple GPS tracking system for my 2 cat

Would one of these do the job?
**broken link removed**
The smallest microcontroller interface on the board still don't look small enough for the kind I need...

To save some money should I just get 1 of these?
**broken link removed**

Also, any help on exactly what PIC I need?

Also! Does an tranceiver or GPS need an aerial? Like the kind of aerial I see hanging out the back of my alarm clock radio. I figured, if it does I can neatly wrap it around the collar itself.