nuisance signals ???

Hello to all I hope I'm in the right forum for some advice.

I have a bank LEDs turned on by a key fob which also starts a millis() function whiich in turn displays the start time on my serial monitor. when the LEDs finish flashing I have a switch (manually operated)that signals the arduino to stop the millis () and display the elapsed time on the serial monitor also. everything works fine . I wanted to replace the switch with a wireless sensor( of sorts) that I have put together using a PIR sensor, NANO,and a 433MHz radio transmitter.I have the receiver on the same arduino UNO as the lights .

now I have tested the sensor arrangement and it works fine. when triggered it brings on a LED on the UNO to signal message received. The problem I'm having is that when I'm not triggering the sensor( no LED on) the serial monitor shows readings that should only be displayed when the sensor is tripped .

Sorry for being a bit long with the explanation of my issue but I want to give as much info. as possible . How can I stop the nuisance readings? is the Antenna picking up stray signals? If so, why is it not bringing on the LED as well as the false reading on the monitor. Any help would be appreciated. Thanks in advance.

You need to post your program AND a wiring diagram showing all your connections.

False triggers are often associated with "floating" inputs - for example using pinMode(pin. INPUT) rather than pinMode(pin. INPUT_PULLUP)

...R

What type of receiver and transmitter and software to send & receive do you have? The 433 is very noisy but you can get good results using say Virtualwire.

You could eliminate noise factor and see if your code works by connecting a direct wire between the two arduinos. So if your first arduino is sending via pin 12 (its has an rf transmitter and the datapin is connected to pin 12) and the other arduino is listening pin 11 (the receiver datapin is at 11) just put a wire bet between the pins: Arduino sender pin 12------->11pin Arduino receiver.

This simulates rf send & receive

Robin2: You need to post your program AND a wiring diagram showing all your connections.

False triggers are often associated with "floating" inputs - for example using pinMode(pin. INPUT) rather than pinMode(pin. INPUT_PULLUP)

...R

Thanks Robin 2, I'll get a diagram together and put the code with it. I have a pull down resistor on the data pin from the receiver to the UNO. I will look at the (pin.INPUT_PULLUP) and hopefully get a result.

newuser: What type of receiver and transmitter and software to send & receive do you have? The 433 is very noisy but you can get good results using say Virtualwire.

You could eliminate noise factor and see if your code works by connecting a direct wire between the two arduinos. So if your first arduino is sending via pin 12 (its has an rf transmitter and the datapin is connected to pin 12) and the other arduino is listening pin 11 (the receiver datapin is at 11) just put a wire bet between the pins: Arduino sender pin 12------->11pin Arduino receiver.

This simulates rf send & receive

thanks newuser. I'll give that a try to see if it can enlighten me. I am using Virtualwire fo rthe radios.

mechup: I have a pull down resistor on the data pin from the receiver to the UNO. I will look at the (pin.INPUT_PULLUP) and hopefully get a result.

A pull-down resistor is probably just as effective as pull-up.

...R