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If you want to see the TTL data, the simplest method is to use a TTL to RS232 converter and use a serial terminal on a computer to see it.
By far the easiest way to see the RF itself is to buy a cheap receiver module and follow the instructions above.
Use a frequency counter, a calibrated receiver or a spectrum analyzer to measure the frequency, there is no other way.
As per my knowledge PC supports for smaller frequency if u want to check it directly. 433 Mhz is very high frequency and u cannot see it on PC, even most common oscilloscopes doesn't support such a high frequency.
The modules are simple AM OOK types, they will work but have poor immunity from interference so don't worry if you see random output when the transmitter is not running.
The receiver output is 0V to 9V which is too high to safely connect to a TTL input, I suggest you take the output through a resistor of 470 Ohms to the input of the MAX232 and add a diode from the MAX232 side to it's 5V supply, cathode (+) end toward the 5V supply. This will protect it from excessive voltage.
The inputs (from the receiver) to the MAX232 are on pins 10 or 11, use the appropriate output to the PC and Hyperterminal or some other similar software to see the data.
The receiver output is 0V to 9V which is too high to safely connect to a TTL input, I suggest you take the output through a resistor of 470 Ohms to the input of the MAX232 and add a diode from the MAX232 side to it's 5V supply, cathode (+) end toward the 5V supply. This will protect it from excessive voltage.
The inputs (from the receiver) to the MAX232 are on pins 10 or 11, use the appropriate output to the PC and Hyperterminal or some other similar software to see the data.
The idea is that you prevent the 9V output of the RX module from overloading the input of the MAX232. The input pin draws very little current so normally the 470 Ohm resistor drops almost no voltage. When the RX output is low (0V) so is the input to the MAX232 but when it goes high (9V) the diode conducts and the current through the resistor is safely dumped into the supply rail while holding the voltage at just a little over 5V.
You can do the same with a Zener diode if you like, use either a 4.7V or 5.1V device, still use the 470 Ohm resistor but this time connect the Zener cathode to the MAX232 input and the anode to ground. There are other ways to achieve the voltage drop but they will be less reliable if the 9V RX supply drops and I'm guessing you are using a 9V battery so such a drop is likely to happen as it discharges.
I try to use that RF 433MHz modules for remote control, but witouth success. I make all, and when I connect remote control TX direct with wire to RX remote control (witouth RF modules) all works, but when I try over RF modules no success, led of RF TX and RX blinks (he transmit data) but nothing happen on remote control receiver outs. I use standard voltmeter to see voltage on RF RX out and shows about 2-3V oscilating with 0,3V. I try to use zener 3,3V and 5,1 on RF RX out but nothing happen on remote control receiver.
Because that I plan to see what happen with sending and receiving codes when RF is used.
For now I testing with PC ATX Power Supply 12V and 5V for RF RX I use 7809 to get 9V, but I plans to use small 12V battery.
The source code uses FSK and the frequency is in the audio range so you should be able to hear the data. Try connecting a small loudspeaker with a 100 Ohm resistor in series across the input to the transmitter and ground and then across the output of the receiver and ground. You should hear a short beep on the line between the transmitter PIC and transmitter module and the same beep at the output of the receiver. You will probably hear hiss at the receiver but the beep should still be audible as data is sent. This will confirm whether the signal is being generated and reaching the receiver, let me know what you hear.
Here is result of captured data for three channels, from Out pin (pin 2) of TX PIC and freeware software what I use for that.
Just to say, I press button of each of three channel for while, about few sec duration each, and that data is in separate log files.
RC works when channel taster is pressed on TX, on RX LED light for that time, when release button LED turned off on RX out.
And later I use second useful program to see RS232 data serialportng.exe and capture two log files for two channels of TX (1ch_serial_log.txt and 2ch_serial_log.txt)
I didnt find hyperterminal is usefull, thise two programs do the great job.
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, can I connect rx over max232 on rs232?
