Assume your receiver's S-meter is calibrated to a standard of 6 dB per S-unit per a recommendation by the International Amateur Radio Union (IARU). The S-meter on your receiver shows S8 when listening to a nearby transmitter. Approximately how much must the transmitter power be raised to increase the reading to S9?

The international standard for amateur radio S-meters states that one S-unit is equal to 6 decibels (dB). To increase your received signal by one full S-unit (for example, from S8 to S9), the transmitter's signal strength must increase by 6 dB. A fundamental rule of RF power and decibels is that a 3 dB increase requires doubling the transmitter power. To achieve a 6 dB increase, the station must double its power twice. Doubling the original power once, and then doubling that new amount again (2 x 2), results in a total power increase of 4 times the original wattage.