The official US Amateur Extra class question pool, with explanations. Post your requests for help, additional explanation, or suggestions for changes to explanations by clicking “Reply” at the bottom of any question.
For questions about the Open Ham Prep site, or about testing in general, please create a new topic in the Community category.
If you have found a bug or have a feature suggestion for the Open Ham Prep app, please create a new topic in the Feedback category.