I want to listen in, but have a birthday dinner this evening. If it finishes by 8:00 I'll probably dial up the reflector. Come to think of it, anyone can dial up the reflector. The process (after confirming the frequency is not in use) is to announce your intent to connect to an IRLP node, dial the IRLP node (9251) on your DTMF pad and then release the PTT button. The IRLP node will anounce it has been connected.
IRLP node 9251 is a "reflector" node. The reflector nodes allow multiple IRLP nodes to connect together at the same time. There are not that many reflector nodes and they do have limits set on how many concurrent connections can be made at one time.
When you are done using the connection it needs to be dropped. The process is to announce your intent to drop the link, dial 73 on your DTMF pad and then release the PTT button. The IRLP node will announce the link being dropped.