Yes, you can. Here's how:
- Go to the newsgroup's homepage on Google Groups.
- Click the Subscribe to this group link near the top of the page.
- Select how you'd like to be emailed when new content is posted to the group. For Usenet groups, you can choose to receive an abridged email with a daily summary of posts or a digest with the full text of all posts made to the group. If you select the full digest, you'll receive one digest for every 25 messages posted to the group.
- When you're done, click the Subscribe to this group button to confirm your choice.