import socket
import time
host = "83.3.12.43" #your servers ip
port = 1111 #your servers port
rcon_password = "rcon_password" #your servers rcon password
command = "say" #command
interval = 7 #in minutes
messages = ['message 1', 'message 2'] #message list
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.connect((host, port))
i = 0
while True:
print("Sending..")
sock.send("\xFF\xFF\xFF\xFFrcon %s %s %s\0" % (rcon_password, command, messages[i%len(messages)]));
i=i+1
time.sleep(60*interval)
You must to have python2.7 installed on the computer you want to run it on.
Just save this code to a *.py file and run it.