Arduino Radio Relay?

Hey everyone, so I read a couple of topics on this but I'm still in need for some help.

I'm currently trying to find a way to have an arduino send a signal to a remote receiver which will in its turn switch a relay so I can have a 12V connection that is switchable. However I am curious to what I need. The distance that needs to be travelled for the RF is about 300meters and a relay will have to switch a 12V for an airpressure valve(already got the valve).

So in short: How can I get an arduino to send a signal over 300 meters to activate a relay?

Thanks for the help in advance!

-Cow

I would suspect you need to share some more information on what is possible for you / what you already threw out.

My first thought would be to bring the Arduino online, assuming you would have internet on both sites.

Internet may work, if you have a connection at both sides.
LoRa will work unless there's a hill or so in between.

Sparkfun says that their RFM69 can manage 500m in the open. Do you have line of sight between the two locations? XBee pros are capable of a mile or so in good conditions; they're more expensive but you can add intermediate units to make up a mesh if conditions reduce your effective range.

Sparkfun says that their RFM69 can manage 500m in the open.

Yet another option indeed. But mind the frequencies: check which frequenc(y/ies) you can legally use in your locality.

Alright a bit of more info: internet is not an option, there has to be a signal send from the arduino to a device hooked to a drone (dji phantom 4 pro) at a max distance of 300meters. line of sight will be open, the drone has to be seen in order for this project to work(some of it is nondisclosure so I can't give all details)

but basically it has to be a radiosignal going from the arduino on the ground to the drone and that will have to switch an air valve.

Costs isn't an issue by the way as its a project for work/internship.

wvmarle:
Yet another option indeed. But mind the frequencies: check which frequenc(y/ies) you can legally use in your locality.

I'm allowed to use any and all frequency, the project is for an internship at the military so I got clearances

You can't piggyback on whatever signal it is that controls the drone itself?

MrCow579:
signal send from the arduino to a device hooked to a drone (dji phantom 4 pro) at a max distance of 300meters. line of sight will be open,

In that case a pair of nRF24L01+ transceivers should work. You would probably need the high-power version with the external antenna at the base station. If you are controlling the drone with a regular 2.4GHz R/C system it is probably using the same technology on the inside.

Have a look at this Simple nRF24L01+ Tutorial.

...R

MrCow579:
I'm allowed to use any and all frequency, the project is for an internship at the military so I got clearances

I doubt that.

Would your internship provider be impressed if you chose a frequency that interfered with an aeroplane landing system ?

I missed the fact (in Reply #6) that this is a military project. Now that I know I will not be offering any further assistance.

...R

PS ... An Arduino could not possibly work for a military project, it costs less than $1m

Robin2:
I missed the fact (in Reply #6) that this is a military project. Now that I know I will not be offering any further assistance.

...R

PS ... An Arduino could not possibly work for a military project, it costs less than $1m

to you that is an Arduino....
to the military it is an D17R3B self perpetuating, frequency receiving drone attached RF release unit with pneumatic interface.

MrCow579:
I'm allowed to use any and all frequency, the project is for an internship at the military so I got clearances

too little information on one point, too much on another.

MrCow579:
Hey everyone, so I read a couple of topics on this but I'm still in need for some help.

I'm currently trying to find a way to have an arduino send a signal to a remote receiver which will in its turn switch a relay so I can have a 12V connection that is switchable. However I am curious to what I need. The distance that needs to be travelled for the RF is about 300meters and a relay will have to switch a 12V for an airpressure valve(already got the valve).

So in short: How can I get an arduino to send a signal over 300 meters to activate a relay?

Thanks for the help in advance!

-Cow

your project has multiple parts.
assuming you have line of sight
assuming you have reception and distance and the signal is received
each thing you want to do is a differnt thing.
you want to SEND a signal with the INTENTION of it being received. by anyone.
you also have the receiver that will receive a signal on said frequency that anyone sends.
you want to verfy that the the signal received is correct
up to this point, you are working with RF signals and testing for them.

now that you have a state of no signal and signal present, you have to use that information.
signal present means to do the next thing
have an output signal change state
have that state change power an FET or Transistor or Relay or SSR or some such device.
have that FET/transistor connected to your solenoid
said solenoid will then change state for... forever ? for an instant? for 500mS ?
upon successful state change, said signal will then revert back to the non-activated state
the solenoid will return (or stay) as needed to save power
reset ? automatically for the next food drop to the refugees this humanitarian mission is for ?
reset when the next food/medicine payload is placed back at base ?

you should be able to use a simple 5v button on a 1k ohm resistor to power said FET/Transitor/RELAY etc to simulate the signal from the Arduino. the Arduino cannot power the solenoid as it does not have enough power, it can only produce a signal.

MrCow579:
well, seeing as there is a no-fly zone over here, it wouldn't matter. its also not an airforce base so there won't be any planes or heli's here. but that was just to say, any off-limit for civs will not be there for me. ofcourse there are limits but thats due to safety, not due to it being illegal :slight_smile:

so, when you press that button and the drone extends it's landing gear and cuts power....interferes with the flight controls... no problem.... the well pump turns on.. the landing lights illuminate the field..... the coffee maker starts brewing... all the radios on base stop working.... and the doors to the Generals Jeep unlock.... but, they weren't flying....

so no problem, you got clearance.

I guess 'no-fly' means different things to each of us.

dave-in-nj:
so, when you press that button and the drone extends it's landing gear and cuts power....interferes with the flight controls... no problem.... the well pump turns on.. the landing lights illuminate the field..... the coffee maker starts brewing... all the radios on base stop working.... and the doors to the Generals Jeep unlock.... but, they weren't flying....

so no problem, you got clearance.

I guess 'no-fly' means different things to each of us.

it means there are literally no planes in the airspace above where this will be used and within a range of 2km. the range of the RF would only be around 300meters, 350meters at max so that would prevent a lot of issues