Which of the following can result in revocation of the station license or suspension of the operator license?

The FCC has transitioned to a fully electronic system for official correspondence and authorizations. Under current regulations, every amateur radio operator must provide and maintain a valid email address with the FCC. If the FCC attempts to contact you regarding a regulatory matter and the email bounces, they can revoke your station license or suspend your operator privileges. The other options represent common regulatory misconceptions. Amateurs are allowed to build and use homemade transmitters without obtaining formal FCC 'type acceptance' or certification, which is a unique and cherished privilege of the amateur service. Additionally, there is no longer a strict requirement to keep a physical paper copy of your license pinned up at your station.