The 50-50 grind is the first grind trick that most skaters learn, and is a great basic skateboard trick to learn. The 50-50 grind is where the skater grinds the ledge or rail with both trucks. The nice thing about the 50-50 is that you can learn to do it on a curb, which is a pretty safe and easy place to practice.
dBi is decibels relative to isotropic radiator which means that the radiator (an antenna, usually) sends the signal equally strong in all directions, including above and below. Such a radiator would have 0 dBi.(I have yet to see an antenna like that -- it may exist only in math theory.).Bi is decibels relative to isotropic radiator which means that the radiator (an antenna, usually) sends the signal equally strong in all directions, including above and below. Such a radiator would have 0 dBi. (I have yet to see an antenna like that -- it may exist only in math theory.).
Serial digital interface uses BNC connectors. Serial digital interface (SDI) is a family of digital video interfaces first standardized by SMPTE (The Society of Motion Picture and Television Engineers) in 1989. For example, ITU-R BT.656 and SMPTE 259M define digital video interfaces used for broadcast-grade video.