I started using some HC-12 module to transmit sensor data one way, one HC-12 being the transmitter the other receiving,
It works quite nicely for a couple of days and then the transmitter stops transmitting (verified with an RTL-SDR dongle).
I found out that I ignored the warning in the docs that if connected to 5V VDD , it would be good too have a Si-Diode in line with VDD, so that the voltage regulator wouldn't die of overheating.
But from measurements it seems the regulator is still regulating
You could insert some Serial.println at interesting points in the programme for debugging and use a third HC-12 as a monitor receiver to see what happens, first.
I was using them in their default config, transmitting at 20dBm.
The transmit rate was one ~40byte message, every second, and it worked nicely for 5-6 days.
Couldn't get them to send anything. They stlll responded to the AT commands correctly when in 'set' mode.
Burned two of them already awaiting a new batch soon.
I just wonder if anyone else observed these early deaths.
No, was just a thought. I used once a shipload of these modules for a client, but had never any problems. But he didn't transmit at a high rate, like you do.
Leo..
Hello, I have the same problem and after several weeks I was lucky enough to detect when it blocks, and that is when the mobile phone is less than 20 cm from the HC-12 and a call or SMS is received.
It is not always blocked when a call or SMS is received, but whenever it has been blocked it is because of having received a call or SMS.
I have isolated the HC-12 away from phones and it has been operational for 20 days without crashes.
Once blocked, I went to AT mode and on some occasions the board does not respond and on other occasions it does respond to the AT command.
When I exit AT mode, sometimes the HC-12 module starts working and sometimes it doesn't.
In short: the only solution I found is to turn off the module by cutting its power. Since the consumption is excessive to power it from an Arduino pin, I am controlling the power through a BJT transistor connected with an 800 ohm resistor to an Arduino pin.
I have not been able to find a way to reset the module other than cutting the power.
Since I consider that it is the same problem that was originally raised, I wanted to contribute my experience and I was also able to identify the cause of the blockage and in my case the way to solve it, since it has been working for more than a month without errors.
I don't think I need to open a new topic.
Mine were permanently damaged, I could not get them back (I can still use them on the receiving side though).
In your own interest I would create your own thread.
However, after matching the antenna, reducing the TX power by 6dB and putting a diode into the Odd line the module has been transmitting for months now.
