current detector with led power on

[Fovakis]

Hi to all !

I have this 3 pole filter in my receiver's last stage. I want to put a led, so when the current is passing through my circuit the led will light on. I need this because my transmitter a lot of time, don't work fine, so i don't know if there any signal going to my receiver.
It is a way to check it.

Any ideas for cheap consuption ?http://i1284.photobucket.com/albums/a578/fovos1/Circuit_zpsb91f9e29.png

[fungus]

Current passing through a wire creates a magnetic field. You can measure it with something like this:

http://www.ebay.com/sch/i.html?_nkw=current+sensor+module

[Fovakis]

Thanks for your help! But, this is so huge for my devices. I need some electronics schematic //maybe with some BJT/FET some resistors and a led

[fungus]

Thanks for your help! But, this is so huge for my devices. I need some electronics schematic //maybe with some BJT/FET some resistors and a led

In that case you probably want something like this where you pass your wire through it:

http://www.ebay.com/itm/230991057211

[Fovakis]

That's is so cool man!! really! but i believe i can do it more simply 

[fungus]

That's is so cool man!! really! but i believe i can do it more simply 

You might need a different diameter/rating ... but simpler than that?  :~

[Fovakis]

yes it is simple.but is cost more that some led and bjt and also it need some weeks to come to my country (Greece). I need to prepare something at this week bro :~

[fungus]

yes it is simple.but is cost more that some led and bjt and also it need some weeks to come to my country (Greece). I need to prepare something at this week bro :~

If all you need is on/off (not measure accurate values) then maybe you can just wrap a coil of wire around your cable. Ground one end, measure the voltage on the other end. That's basically all those sensors are.

nb. Be sure to put a resistor between the coil and the Arduino pin.

[tocpcs]

How many turns is needed?

[fungus]

How many turns is needed?

Depends on the strength of your magnetic field.

[KeithRB]

You give no details about the transmitter, but you might try a neon bulb. Just connect it to the output with a series resistor. If the RF gets above 50V it will light. a simple high impedance detector probe might work, too.