On most Linux server enviroments, you can simply run the command below as often as you are comfortable. We recommend that you run it every 120 minutes or less. On a busy site, you might want to run it every 80 minutes. The more frequent you run it, the less load it will be on the server, but the invite sending will also be faster.

Cron can be set up by using any one of below given  methods lynx OR wget

A) lynx is a text based browser that is installed in most hosting environments.  

Broadcast has three crons  

Below xxxx=Private Cron Key in Backend option of Broadcast
sitename="Your sitename"

Cron URL for fetching status updates from facebook,linkedin,twitter to your site

lynx -source "http://sitename/index.php?option=com_broadcast&controller=broadcast&task=get_status&tmpl=component&pkey=xxxx" > /dev/null

Cron URL to broadcast status from site to facebook,linkedin,twitter

lynx -source "http://sitename/index.php?option=com_broadcast&controller=broadcast&task=set_status&tmpl=component&pkey=xxxx" > /dev/null

Cron URL for getting RSS feed

lynx -source "http://sitename/index.php?option=com_broadcast&task=getrssdata&controller=rss&tmpl=component&pkey=xxxx" > /dev/null 

B) wget If you do not have lynx installed, you can use other alternatives such as wget as below.

Broadcast has three crons  
Cron URL for fetching status updates from facebook,linkedin,twitter to your site

wget -O /dev/null "http://sitename/index.php?option=com_broadcast&controller=broadcast&task=get_status&tmpl=component&pkey=xxxx" > /dev/null

Cron URL to broadcast status from site to facebook,linkedin,twitter

wget -O /dev/null "http://sitename/index.php?option=com_broadcast&controller=broadcast&task=get_status&tmpl=component&pkey=xxxx" > /dev/null

Cron URL for getting RSS feed

wget -O /dev/null "http://sitename/index.php?option=com_broadcast&task=getrssdata&controller=rss&tmpl=component&pkey=xxxx" > /dev/null