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.
A Ringback Tone is that ringing sound you hear when you try to call someone. Your carrier network provides this sound to your callers when they are trying to connect to you. With LISTEN, you have the option to replace that ringing sound with music or voice status messages.