.. optical fiber to indicate the presence of light, its direction of travel, and the presence of combinations of low-frequency test tone modulation. Its purpose was to positively identify a particular optical fiber in a manhole or ...
.. a system's specifications call for a lowpass filter with a steep frequency-cutoff characteristic, an engineer can opt for a “brick-wall”- filter design that features ...
.. turns on the upper LED. If both LEDs must appear to be on, your program can cycle the port pin between one and zero with a frequency greater than 50 Hz. To calculate the value of the resistor, the following formulas apply for Figure 1a: ...
.. consisting of U2b driven by positive feedback. From U2c through C1 and negative feedback through R1, generating: Pump frequency will vary somewhat with component tolerance and loading of the 10 V outputs, but since the clock ...
.. drive waveform, leaving the P-channel FET in its linear operating region for an extended period and thus limiting switching frequency and causing significant power losses in the cascaded FETs. Figure 2. An N-channel FET driver (a) has ...
.. fuse and R1 is the 7D741 varistor to absorb high voltage transients. C2 is a 100 nF X2 rated capacitor to reduce the high-frequency noise and T1 is a common mode choke. BR1 is the Vishay MB6M bridge rectifier and C3 is a 22 ... .. a gap accurately and winding the transformer by hand and without any error is difficult. The easy solution is to use an LCR meter! first, wind the primary and assemble the transformer (without any gap). Then measure the inductance of the ...
.. 1. Mains sine wave (Green arrows show the zero crossing points). The Figure 1 shows the mains sinusoidal wave with the frequency of 50 Hz (sometimes 60 Hz). To build a dimmer, the zero crossing points (the points where the wave ...
.. of noise filtering and has negligible effect on the switching of Q 3 . You may need C 1 and R 5 to roll off Q 2 ’s frequency response to avoid the possibility of high-frequency oscillation. The transistor types are not critical; ...
.. determines the transmission power which of course affects the detection range. The potentiometer R5 adjust the frequency. If you have an oscilloscope, you should be able to see a signal like the Figure 4 at the U1, pin-3 ...
.. works. The R1C1 time constant couples the V IN /ppv square wave found at U1pin14 to U1pin9, creating an F PUMP oscillator frequency of (approximately): During the F PUMP negative half-cycle (U1pin4 = 0), the upper (U1pin14) end of C2 ...