What to do if ARTEX Transmitter shows 3-Flash?
- AAmy HarrisonAug 2, 2025
A 3-Flash indicates a 406 MHz transmission problem. You should verify the coax cable/antenna is connected and in good condition. Perform continuity check of center conductor and shield and check for a shorted cable. Check with a VSWR meter. Check antenna for opens, shorts, or a resistive ground plane connection. Lengthen or shorten antenna coax cable length by 4 to 6 inches. Provide a ground plane at least 12 inches in diameter. Stay at least 10-12 inches away from upright metal structures. Verify 406 MHz programming. If the transmitter module is faulty, it cannot be repaired in the field and should be returned to the factory for servicing.