Problem sending data with 433MHz transmitter and receiver

Hello! I want to use RF modules ( transmitter and receiver ) to send commands from Serial Monitor to another arduino via the RF modules to switch on/off a relay module. I’m using the Virtual Wire library, and i’ve got stuck with the code ( i’ve used the example code from a site as a base code ). This is my code so far:

Transmitter:

#include <stdlib.h>
#if ARDUINO >= 100
  #include <Arduino.h>
#else
  #include <wiring.h>
#endif
#include <VirtualWire.h>

int radio = 12; // The radio pin

void setup(){
  
Serial.begin(9600);

  pinMode(radio, OUTPUT);
  vw_set_tx_pin(radio);  // Setting the transmission pin to the radio pin
  vw_setup(2000);
}



void loop(){
  
 char on = '1';          // I couldn't get it working with words so i just used 0 and 1 as commands
 char off = '0';
   delay(1000);
  char res = Serial.read();
 
  if (Serial.available()){
    
    if (res == '1'){
vw_send((uint8_t *)on, 1);
Serial.println("Command sent! On!");
    }
    
    else if (res == '0'){
    vw_send((uint8_t *)off, 1);
    Serial.println("Command Sent! Off!");
    }
    
    


  
  }
}

Receiver:

#include <VirtualWire.h>


const int relay_pin = 7;
const int receive_pin = 11;


void setup()
{
  pinMode(receive_pin, INPUT);
    delay(1000);
    Serial.begin(9600);	// Debugging only
    Serial.println("setup");

    // Initialise the IO and ISR
    
    vw_set_rx_pin(receive_pin);
    
  
    vw_setup(2000);	 // Bits per sec

    vw_rx_start();       // Start the receiver PLL running
}

void loop()
{
  
    uint8_t buf[VW_MAX_MESSAGE_LEN];
    uint8_t buflen = VW_MAX_MESSAGE_LEN;

    if (vw_get_message(buf, &buflen)) // Non-blocking
    {
      char(buf);
	if (buf == '1'){

            digitalWrite(relay_pin, HIGH); // Turn on the relay module
}
        else if (buf == '0'){

            digitalWrite(relay_pin, LOW); // Turn off the relay module
}
        }
        
    
    }





}

What RF modules are you using?

…R

Transmitter: TWS-DS-6
Receiver: RWS-371-6

Please post links to the datasheets for your modules.

...R

Transmitter: http://www.wenshing.com.tw/Data_Sheet/TWS-DS-3_433.92MHz_Miniaturization_Wireless_Transmitter_Module_Data_Sheet.pdf

Receiver: http://www.wenshing.com.tw/Data_Sheet/RWS-371-6_433.92MHz_ASK_RF_Receiver_Module_Data_Sheet.pdf

I am not familiar with those modules.

I think you would get a better response if you edit your Original Post and change the Title to "Problem sending data with 433MHz transmitter and receiver"

...R