Ask your doctor for a vitamin D test. Be specific and ask for a 25(OH)D test. There is another type of blood test for vitamin D, called a 1,25(OH)âD test, but the 25(OH)D test is the only one that will tell you whether youâre getting enough vitamin D. Order an in-home test. These tests are sent to your home.
Carrier signal: A frequency in a communications channel modulated to carry analog or digital signal information. For example, an FM radio transmitter modulates the frequency of a carrier signal and the receiver processes the carrier signal to extract the analog information. An AM radio transmitter modulates the amplitude of a carrier signal.
1 The information is provided to the transmitter either in the form of an audio signal, which represents sound, a video signal, or for data in the form of a binary digital signal.  In an AM (amplitude modulation) transmitter the amplitude (strength) of the carrier wave is varied in proportion to the modulation signal.