When may amateur radio operators use their stations to notify other amateurs of the availability of equipment for sale or trade?
Never
When the equipment is not the personal property of either the station licensee, or the control operator, or their close relatives
When no profit is made on the sale
When selling amateur radio equipment and not on a regular basis✓Correct answer
Explanation
The exception is narrow: the gear must be apparatus normally used in an amateur station and the activity must not become routine. Whether you make a profit is not the test, and the equipment may be your own.