Radio wave frequency (band) division table 
Note: "High frequency" is a relative concept. "High frequency" in the above table is a narrow concept, referring to the short-wave band, whose frequency range is 3 ~ 30MHz, while the general term "high frequency" refers to Radio frequency, its frequency range is very wide, as long as the circuit size is much smaller than the operating wavelength, it can be analyzed and realized with concentrated parameters, which can be considered to be "high frequency" (in terms of current technology, the upper limit frequency of "high frequency" can reach 3GHz).
Incremental encoders provide speed, direction and relative position feedback by generating a stream of binary pulses proportional to the rotation of a motor or driven shaft. Lander offers both optical and magnetic incremental encoders in 4 mounting options: shafted with coupling, hollow-shaft, hub-shaft or bearingless. Single channel incremental encoders can measure speed which dual channel or quadrature encoders (AB) can interpret direction based on the phase relationship between the 2 channels. Indexed quadrature encoders (ABZ) are also available for homing location are startup.
Incremental Encoder,6Mm Solid Shaft Encoder,Hollow Rotary Encoder,Elevator Door Encoder
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