Home » Regulations » 17 » b An amateur station may transmit unidentified signals:   a.   when making a brief test not intended for reception by anyone else   b.   when conducted on a clear frequency when no interference will be caused   c.   when the meaning of transmitted information must be obscured to preserve secrecy   d.   never, such transmissions are not permitted Your answer "b" is not correct. "d" is the right answer. Next