GRPS Tracker

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spot
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GRPS Tracker

Post by spot »

It's not a GPS tracker, all it can do is very roughly estimate its distance to proximal cell towers and calculate the geometry. It's usually off by as much as 500 metre/yards so you can't use it for navigation.

The GF-07 box is an inch and a half along the longest axis, weighs an ounce, clings to any metal surface by using an internal magnet, and it's absolutely slated by every review out there on the web. There's two reasons for that.

Three reasons. Or maybe four, we'll see. The imprecise location is one.

It requires a SIM and a micro-SD card to accumulate time-and-place pairs for mapping. That's the second reason, either "it didn't come with a SIM" or "I had to buy a micro-SD card". This thing is sold worldwide, I've no idea how anyone thinks a SIM is packaged with it and SIMs are free where I live anyway. A 4 or 8 GB micro-SD card is the price of a small bar of chocolate.

So to the third reason. SIMs often arrive with a SIM lock code which needs a PIN each time you power it up. There's no numeric pad on the GF-07 and it's intended for remote use anyway. Clearly you have to put your SIM into a phone, activate it, write down the phone number, remove all the security and then transfer it into the device, it's how things work.

You SMS codes in the format nnn and it sends a reply confirming it's actioned the command. If you get a response then you activated the SIM correctly, if you don't then repeat the previous step less wrongly, you'll get there in the end.

So, what will it do. It lets you remotely turn on the microphone and listen/record from the device. It lets you talk and be heard, allegedly - I've not tried that. You can ask where it is on the planet and narrow it down to a quarter mile. You can get it to SMS you every time it's picked up or moved in any way, and send you a recording whenever it hears any sounds. It runs for a week on one charge. It does actually do all of these things and it costs £4 delivered.

How it ever gets even one bad review I have no idea. If I want the correct location on a 5 metre grid then I expect to pay more, not least for a larger battery. There are devices with better precision and longer battery life, but not for £4.

People are just strange.
Nullius in verba|||||||||||
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Who has a spare two minutes to play in this month's FG Trivia game!
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Bryn Mawr
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GRPS Tracker

Post by Bryn Mawr »

spot;1528218 wrote: It's not a GPS tracker, all it can do is very roughly estimate its distance to proximal cell towers and calculate the geometry. It's usually off by as much as 500 metre/yards so you can't use it for navigation.

The GF-07 box is an inch and a half along the longest axis, weighs an ounce, clings to any metal surface by using an internal magnet, and it's absolutely slated by every review out there on the web. There's two reasons for that.

Three reasons. Or maybe four, we'll see. The imprecise location is one.

It requires a SIM and a micro-SD card to accumulate time-and-place pairs for mapping. That's the second reason, either "it didn't come with a SIM" or "I had to buy a micro-SD card". This thing is sold worldwide, I've no idea how anyone thinks a SIM is packaged with it and SIMs are free where I live anyway. A 4 or 8 GB micro-SD card is the price of a small bar of chocolate.

So to the third reason. SIMs often arrive with a SIM lock code which needs a PIN each time you power it up. There's no numeric pad on the GF-07 and it's intended for remote use anyway. Clearly you have to put your SIM into a phone, activate it, write down the phone number, remove all the security and then transfer it into the device, it's how things work.

You SMS codes in the format nnn and it sends a reply confirming it's actioned the command. If you get a response then you activated the SIM correctly, if you don't then repeat the previous step less wrongly, you'll get there in the end.

So, what will it do. It lets you remotely turn on the microphone and listen/record from the device. It lets you talk and be heard, allegedly - I've not tried that. You can ask where it is on the planet and narrow it down to a quarter mile. You can get it to SMS you every time it's picked up or moved in any way, and send you a recording whenever it hears any sounds. It runs for a week on one charge. It does actually does all of these things and it costs £4 delivered.

How it ever gets even one bad review I have no idea. If I want the correct location on a 5 metre grid then I expect to pay more, not least for a larger battery. There are devices with better precision and longer battery life, but not for £4.

People are just strange.


I’ll not ask what you’re wanting to track but I do have two questions:-

Is the signal strong enough to escape a not too efficient Faraday cage?

Can you wire it to a permanent charger?
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spot
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GRPS Tracker

Post by spot »

Bryn Mawr;1528221 wrote: I’ll not ask what you’re wanting to track but I do have two questions:-

Is the signal strong enough to escape a not too efficient Faraday cage?

Can you wire it to a permanent charger?


I'd need a car to check but.

It has a SIM, and all the other trackers have SIMs too, so I think it's a reasonable prediction that it can get a signal out of a wheel arch, say. Or even a boot, who knows. It needs tapping onto a 5v supply line from the engine compartment, 12v or 24v with an inline step-down Zener diode circuit. So yes, you need to run a thin wire pair to wherever the signal will emerge and you get a text whenever the car is moved.

Or bike. Far easier on a bike.
Nullius in verba|||||||||||
To Fate I sue, of other means bereft, the only refuge for the wretched left.

Who has a spare two minutes to play in this month's FG Trivia game!
My other operating system is Slackware
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Bryn Mawr
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GRPS Tracker

Post by Bryn Mawr »

spot;1528222 wrote: I'd need a car to check but.

It has a SIM, and all the other trackers have SIMs too, so I think it's a reasonable prediction that it can get a signal out of a wheel arch, say. Or even a boot, who knows. It needs tapping onto a 5v supply line from the engine compartment, 12v or 24v with an inline step-down Zener diode circuit. So yes, you need to run a thin wire pair to wherever the signal will emerge and you get a text whenever the car is moved.

Or bike. Far easier on a bike.


Inside the cab, you need to be able to hear what the thieving scum are saying and, if you can wire the sound output into the car’s speakers, tell them that they’re being tracked and the police are on their way.
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spot
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GRPS Tracker

Post by spot »

Two solder points available, but I'm not sure how you override the on/off, channel selector and volume control of the sound system even if you added an audio-input bluetooth terminator to those points.

But the eBay title does say "Real Time Tracking Locator Device For Car".
Nullius in verba|||||||||||
To Fate I sue, of other means bereft, the only refuge for the wretched left.

Who has a spare two minutes to play in this month's FG Trivia game!
My other operating system is Slackware
User avatar
Bryn Mawr
Posts: 15981
Joined: Mon Feb 27, 2006 4:54 pm

GRPS Tracker

Post by Bryn Mawr »

spot;1528225 wrote: Two solder points available, but I'm not sure how you override the on/off, channel selector and volume control of the sound system even if you added an audio-input bluetooth terminator to those points.

But the eBay title does say "Real Time Tracking Locator Device For Car".


Bluetooth link would be fine, you can set it up to override the radio with its own volume setting. In my car I always have the radio on but at zero volume to show the satnav map.

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