This article explains how to setup a traditional telephone conference call, where participants can call in to a specific number on their phone. Participants do not have to be on campus nor do they need an SNC email account.
Every event on a Google calendar includes the "Google Meet" option and "Zoom Meeting" option, so start by scheduling a new event on your calendar for the date/time of your call. To add either option, first select the "Add video conferencing" button while creating or editing the event.
After you click that button, you can choose one of the following options to create the meeting.
After you have created and saved the event, click on the event while viewing your calendar. The event details will pop up, like this:
Notice that the above popup includes the "Join by phone" information for the Google Meet. This shows you the telephone number for participants to call, along with the PIN they'll have to enter. That's it.
For the Zoom meeting, the blue phone number next to the phone icon will be the number participants will call along with the Passcode right beneath it that they will have to enter.
While you can invite all of your participants via the calendar, you can also just email everyone and give them the phone number and PIN. There is no cost to use this call-in feature.