I'm looking to build a long distance (up to 425 meters) wireless remote transmitter and receiver. It needs to operate on battery power. I want to use the transmitter to open and close a circuit. How can I do this?

Thank you!

 

A cheap (but not too cheap) pair of walkie-talkies could accomplish this. I have some that can send a tone, for instance. All you'd need to do is add a circuit to react to that tone. It's possible these walkie talkies light an LED when they're receiving a signal. If so, you could tap into that.

There are many other options. More details will get a better answer. Be aware that some radio options are prohibited by local laws. You should specify where you need this to work.

 

A cheap (but not too cheap) pair of walkie-talkies could accomplish this. I have some that can send a tone, for instance. All you'd need to do is add a circuit to react to that tone. It's possible these walkie talkies light an LED when they're receiving a signal. If so, you could tap into that.

There are many other options. More details will get a better answer. Be aware that some radio options are prohibited by local laws. You should specify where you need this to work.

Thanks for your response! This will be used in Texas. When you say cheap but not too cheap do you mean like $50/$75 or over $100?
So, if I get a set of walkie talkies that have an LED indicator light, I could potentially just take the wires off the LED and add them as part of the circuit?

 

Thanks for your response! This will be used in Texas. When you say cheap but not too cheap do you mean like $50/$75 or over $100?

Correct. I was thinking of something like this:
https://www.ebay.com/i/191827070352?chn=ps&dispItem=1
I have some similar to those (they're were handy in the days before cellphones, for skiing and mountain climbing). They can transmit ring tones.

So, if I get a set of walkie talkies that have an LED indicator light, I could potentially just take the wires off the LED and add them as part of the circuit?

That's also what I was thinking, but I haven't seen a specific device that I know would work and the devil is always in the details. I'm sure you could rig something to identify a particular tone signal that the talkies can generate but I'm not sure there is a talkie that lights an LED in response to receiving a strong signal. Seems like there should be but I haven't seen one.

 

I'm looking to build a long distance (up to 425 meters) wireless remote transmitter and receiver. It needs to operate on battery power. I want to use the transmitter to open and close a circuit. How can I do this?

Thank you!

See if this suits your needs:

https://www.allaboutcircuits.com/pr...enting-the-hc-12-wireless-transceiver-module/

 

Absolutely best solution here ought be Nordic NRF024L for about 1 USD per piece. Warranted clear field distance on FSK above 1000 meter, measured in city centre conditions about 500 meter.
http://www.ebay.com/itm/2PCS-Arduin...237154&hash=item2eecd43ead:g:MZYAAOSwEeVZexSe
If the distance seems too weak, then use instead the about twice expensiver (the same ebay) system LoRa. It complects has successful work in the city centre situation about 3000 meters afar.

 

Absolutely best solution here ought be Nordic NRF024L for about 1 USD per piece. Warranted clear field distance on FSK above 1000 meter, measured in city centre conditions about 500 meter.

Well what do you know, I have one of those too. https://www.allaboutcircuits.com/projects/create-a-2-channel-remote-control-with-the-nrf24l01/

You're right that the price can't be beaten -- but I find the HC12 easier for novices to use and integrate into projects

 

These are excellent solutions since the TS did say he wants to build a solution. I tend to avoid building except as a last resort.