How can I use a radio wave to turn on/off a siren?

AI Thread Summary
To turn a siren on and off using radio waves, a low-power radio transmitter circuit can be designed, but it has a limited range of 10m-20m and requires tuning to an open frequency, which can be challenging in crowded areas. A suggested approach is to use a cheap radio receiver that can detect a specific tone frequency from the transmitter. Alternatively, using an infrared (IR) link or a garage door opener system is recommended, as these provide a more secure method with coded signals for activation. Wireless modules from companies like Link Technologies can be utilized to connect a relay for switching the siren. This method enhances security and reduces the risk of hacking.
Harmony
Messages
201
Reaction score
0
How can I use radio wave to turn on/off a siren? I think it is possible for me to design a radio signal through this schematic:
http://www.aaroncake.net/circuits/fmtrans.htm

The problem is, how do I design a receiver that can switch on a siren by receiving the radio signal?
 
Engineering news on Phys.org
You could use a cheap radio receiver, and just bandpass the audio output to look for the tone frequency that you would be transmitting.

The circuit you show is for a typical low-power, unlicensed radio transmitter. The range of these transmitters is about 10m-20m, so don't expect too much. You also have to tune them to an open station frequency, so if you are in a highly-populated area with lots of FM radio stations, you will have trouble finding an open frequency.

You might consider using an IR link instead of FM. You could start with a kit, like the one in the lower right corner of this page:

http://www.transeltech.com/kits/kits1.html
 
Last edited by a moderator:
Try a garage door opener system

Try using a garage door opener system.
Two reasons.
1-you need a transmitter on a set frequency that trans mits a code
2-you need a receiver that receives a set frequency that needs a code to turn the power on.
Instead of the door opening and closing you could have the sireen latch on or off and the security of any hacker reduced.
good luck
 
you would get ready wireless modules from Link Technologies they make ready modules you can further connect a buffer relay to switch on / off the siren

Rick
 
Last edited by a moderator:
Hi all, i have some questions about the tesla turbine: is a tesla turbine more efficient than a steam engine or a stirling engine ? about the discs of the tesla turbine warping because of the high speed rotations; does running the engine on a lower speed solve that or will the discs warp anyway after time ? what is the difference in efficiency between the tesla turbine running at high speed and running it at a lower speed ( as fast as possible but low enough to not warp de discs) and: i...
Thread 'Where is my curb stop?'
My water meter is submerged under water for about 95% of the year. Today I took a photograph of the inside of my water meter box because today is one of the rare days that my water meter is not submerged in water. Here is the photograph that I took of my water meter with the cover on: Here is a photograph I took of my water meter with the cover off: I edited the photograph to draw a red circle around a knob on my water meter. Is that knob that I drew a red circle around my meter...
Back
Top