I have recently made RC car using HT12E and HT12D connected to a cheap ASK RF module of 433 MHz frequency,but it's range is not good only a few meters and also so prone to electrical noise generated from DC motors,I have tried every solution like covering motor with metal chasis which is connected to ground and low pass filter….but nothing works so finally decided to change frequency,found this
but unlike normal module,it has 6 pins,I know it's transreceiver so I will buy two pcs but how to use them with HT12E and HT12D,what are PROG and CTS pins and how to use them?
Electronic – use this rf module with HT12E and HT12D
433mhzdecoderencoderRF
Related Solutions
I see you do not have jumpers to join each side of the power rails. Note there is a gap on both sides down the middle for the Blue and Red outer rails.
Remember I said check power? That means you need an inexpensive multimeter to do this.
Best practice of using the breadboard is to use short solid wire leads and neatly connect flush to the board without large inductive loops. Keep IC's close toegether and imagine that it is a printed circtuit board layout. Add decoupling caps close to the IC. Avoid long jumper wires at all costs.
For fun here is a free tool to help design, layout and simulate. http://fritzing.org
I've never tried this before but looks ok.. Use staples for power and ground rails. Don't use wire with thick insulation. Try to get thin solid wire 24 AWG I believe. and lay down flat.
Firstly look how I've modified the power and ground leads below (in red): -
It's important to star-point different circuit blocks back to their respective batteries in order to minimize loop current emissions. The important one is the 12V local to the L293D chip. Talkingof which, be sure to use the version with a "D" on the end because that has internal flyback diodes and without these you'll be producing voltage spikes that could interfere with tesla coils (that was a joke that last bit).
Next are decoupling capacitors across each motor - If you are using PWM control you need to be a bit cautious with high values as these will suck energy from the pulse width modulation. Try 10nF across each motor and if necessary try a 10uH inductor in series with each motor with a bigger cap (like 100nF) still directly across the motor.
The problem could be also solved by making the whole of the 0V system a local earth plane - there may still be currents flowing in your current set-up that cause the HT12D to glitch and lose control.
Make sure you have all the major electronic components decoupled with caps too. Maybe 10uF and 10nF across the HT12 and L293D and receiver. HT12 and receiver should be close together and have as a minimum a shared local earth plane.
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Best Answer
According to the datasheet that module has an async UART interface so it won't be compatible with the HT12E and HT12D. Those are designed to interface with "dumb" RF modules that have a simple data input and output that don't implement any higher level protocols.
I'd suggest attempting to debug your existing solution further or try some alternative transmitter / receiver modules. In my experience the 433MHz modules are normally good for around 20-50 meters at least if the power supply is clean and you have a relatively decent antenna.
Maybe just as a test you could try powering the HT12D / receiver (I assume that's on the motor side?) from a seperate power supply like a battery and see how that goes. I'm guessing if your range is that low with those modules unless they have a defect you may have the same problem with different modules / frequencies.