# how to build this?

#### talzer

Joined Dec 13, 2008
8
im not so good in electronics but can i know how to build of these thing?

just helping my son in some simple project. just in case there are information that can be provided here, i might help him out a bit.

thanks

#### mik3

Joined Feb 4, 2008
4,843
When is that thing flashing?

#### Brother_of_the_wind

Joined Dec 7, 2009
3
Looks like they are using a simple pic with a single RGB LED. It will require a programmer so it may not be doable in your situation.

Les...

#### talzer

Joined Dec 13, 2008
8
basically this thing will flash when they is an incoming call
i believe it is activated by some sort of phone signal but i'm not sure with the component inside it.

#### SgtWookie

Joined Jul 17, 2007
22,210
This is somewhat of a paradox.

I could see that the flashing LED could be very useful to alert a hearing-disabled (aka deaf) person to alert them to an incoming call.

But why alert a deaf person to an incoming call from a cellular telephone?

Of course, text message alerts, etc - would certainly be apprapos.

This thing may likely be brand-specific.

#### Audioguru

Joined Dec 20, 2007
11,249
Cell phones stores sell many flashing antennas. I think it has a rectifier that is powered from the transmitted signal. The cell phone transmits that it is turned on when it is ringing from an incoming call.

#### talzer

Joined Dec 13, 2008
8
can you be more specific on the rectifier, and the components involved?
so basically this thing no need batteries?

#### CDRIVE

Joined Jul 1, 2008
2,219
Cell phones stores sell many flashing antennas. I think it has a rectifier that is powered from the transmitted signal. The cell phone transmits that it is turned on when it is ringing from an incoming call.
Good call.

#### BMorse

Joined Sep 26, 2009
2,675
can you be more specific on the rectifier, and the components involved?
so basically this thing no need batteries?

quite a few of these devices I have come accross use a couple of small button cell batteries.... if not, it would have to be pretty close to the antenna of the cell phone (some devices that replace your existing cell phone antenna which light up when the phone rings, most of those do not have batteries)...
They battery less ones work almost similar to an RFID tag, when a certain frequency is picked up by the RF coil, it converts this to power to flash the LED....

My .02

#### mkbutan

Joined Sep 30, 2008
277
BMORSE is right
They battery less ones work almost similar to an RFID tag, when a certain frequency is picked up by the RF coil, it converts this to power to flash the LED....
yes
you are right; it is a microwave receiver without a battery
when there is an incoming or outgoing call the coil near to cellphone it get energize & start blinking with the help of 1 transistor;capacitor;LED all SMD's

#### mkbutan

Joined Sep 30, 2008
277
There is no spoon -Neo-
Disclaimer: The example programs,circuits, projects and information I provide or post on this web site are for educational purposes only. By copying anything from this site posted by me, you agree to the "as is" nature of the programs, circuits, information and to the statements listed in this disclaimer.No warranty or liability is expressed or implied. Working with AC /DC voltages can be dangerous and even deadly. Proceed at your own risk!

Good i like it

#### CDRIVE

Joined Jul 1, 2008
2,219
I'll admit that the luminescence in the video seems quite substantial but I would think a NE2 would light if placed near the antenna.

#### talzer

Joined Dec 13, 2008
8
although i can't understand certain electronic terms here, but will try to digest them lol

thanks for the respond
is these possible components pricey in the market?

#### BMorse

Joined Sep 26, 2009
2,675
although i can't understand certain electronic terms here, but will try to digest them lol

thanks for the respond
is these possible components pricey in the market?

I am not sure how much they are going for in the market, but I just ordered some samples from the company for free (4 pcs) !
I have always been intrigued by these detectors and I have never messed around with RF circuits, so this will be my first project involving RF detection.

#### talzer

Joined Dec 13, 2008
8
can anybody provide examples of schematic diagram to test it out?

#### BMorse

Joined Sep 26, 2009
2,675
this is the basic hookup for this IC....
apparently the cost for the IC is anywhere between $1.25 to$1.31 depending on model...

#### Attachments

• 4.2 KB Views: 36
• 6.9 KB Views: 19

#### BMorse

Joined Sep 26, 2009
2,675
Just got my samples in today so tonight I will see about getting these mounted on something to test them.... pretty small for bread boarding, plus extra capacitance in the breadboard might cause issues.... so I will have to break out one of my trusty Dremmel's and get carving a PCB adapter for it...

#### Ron H

Joined Apr 14, 2005
7,014
I'll admit that the luminescence in the video seems quite substantial but I would think a NE2 would light if placed near the antenna.
Wouldn't that require an electric field strength on the order of 100V/mm (100kV/meter)?

#### BMorse

Joined Sep 26, 2009
2,675
Well, just ran a PCB for the sample IC, it was a little pain in the a\$% to solder the IC on but got it done.... now just have to plug it into a breadboard connect it to the scope and see what I've got!

Although, If it does work, it will be going hay wire with signals coming from the WiFi routers and my daughters phone calls (2.4Ghz cordless phone) and texting (cell phone) all at the same time.... I guess I will have plenty of signals for testing