How to do a Out of Zone detector

[reckless]

Hi All,

I would like to ask about this project

I like a build a transmitter and receiver. Hopefully the transmitter is trasnmitting a constant code , The receiver picks up this code ..do nothing

Once these two pairs are out by maybe 2 to 5metres , the receiver will make a Buzzer to sound and maybe LED to lightup,,

Scenario : Mommy put receiver at wrist .Son wear the transmitter on wrist too. GO shopping ,son playfully run away to see toys and lost her mommy .
Once 'out of range' between the 2 , mommy wrist buzzer n LED will light up.

Is it simple to do these 2 parts? I just need the TXM to produce some ''codes'' to identify its receiver which maybe check for same ''codes'' to tell that these 2 are a pair . Once out of zone, one of them buzz

what components must I need? Anybody tried this stuff before and likes to share experiece or circuit designs?

What is transceivers?? can they do the job better than txm or recv?

I hope there is no PIC control here as I am not very knowledgable with PIC


Anybodylikes to help me out ?



WIth regards,
B

 

[gromikov]

Angel Alert child distance monitor is an early warning system that automatically detects when a child strays too far from adult supervision. Can also be used to protect laptops, briefcases, purses and other valuables. Easy to use; reliable technology. Ideal for malls, airports, theme parks, busy urban areas and other populated locations.

* An early warning alarm system that detects when a child strays too far from adult supervision
* Ideal for malls, busy urban areas, theme parks, airports or wherever you might loose track of a child
* Activated when pulled apart into 2 small, lightweight easy-to-wear units, one for adult, one for child
* Child wears transmitter, adult wears receiver; an alarm sounds on the adult's receiver when the child strays too far
* Child's transmitter has a panic button
* Can also be used to protect laptops, briefcases, purses and other valuables
* Reliable, exclusive technology provides peace of mind
* Comes with 2 neck cords (adjustable adult's and child's safety breakaway version), 2 large and 2 small metal clips, and 2 replaceable long-life lithium cell batteries
* Unit dimensions: 1-5/8"W x 1/2"D x 3-5/8"H
* Product is designed for use with the provided neck cords or clips and not by holding in hand
* Model No. 82562
* Also available in Wal-Mart stores

**broken link removed**

 

[reckless]

Thank you for replying.

I checked on the internet and I know this stuff exist.

I would like to know how the internal circuitries of the transmitter and the receiver if possible.

Does anybody knows? I hope to build it but not sure is it complicated abd what are the components

Help anyone?


thanks

 

[Sceadwian]

I shudder to think that the same device marketed for use in protecting a child also contains a bullet that says

* Can also be used to protect laptops, briefcases, purses and other valuables

Although not technically a parent, I have a 10 year old stepson 3 nephews and a niece, and it makes me sick to think that any responsible living person would rely on a device like this to assure themselves of a child's presence. Sight sound and touch are the only way to determine the location of a child.

 

[3v0]

I shudder to think that the same device marketed for use in protecting a child also contains a bullet that says

Although not technically a parent, I have a 10 year old stepson 3 nephews and a niece, and it makes me sick to think that any responsible living person would rely on a device like this to assure themselves of a child's presence. Sight sound and touch are the only way to determine the location of a child.

There is a use for a product like this. Attach a stungun to the reciever and shock the parent each time the child is allowed out or range.

 

[Sceadwian]

Now you're talking.

 

[gromikov]

Thank you for replying.

I checked on the internet and I know this stuff exist.

I would like to know how the internal circuitries of the transmitter and the receiver if possible.

Does anybody knows? I hope to build it but not sure is it complicated abd what are the components

Help anyone?


thanks

Hi,

First of all you have to make a FM transmitter (with a short antenna or with a wire as an antenna).

Here is the link for FM Circuits:
**broken link removed**

I think it's easier if you want to do this just like a project with non sale purpose, then you can take an old walkman with fm radio..... the most of them indicate the signal strength with a red LED that turns on when detecting a strong radio signal.

If you take just the Radio circuit from the walkman, taking of the LED and connecting the + cable to one port or input pin of your PIC and the otherone to GND then you will be able to know when certain signal is there o not… for example if the PIN ''X'' of your PIC is low, the signal is not beeing received and if it is high then the signal is inside the range.

When detecting the signal is important that the signal is TTl before connecting it to the PIC input.

with other port or pin of your PIC you can control a buzzer or an alarm in the case input(ex led cable) is low, output(alarm) is high and in case input is high, output is low.

I hope you understand the idea .... Sorry for my english hehehe..

If you have questions please contact me.

Greetings