34 results about "Multivibrator" patented technology

The utility model discloses an ultra-high-speed picosecond pulse rising edge generator, which relates to the technical field of power electronics and comprises an oscillating circuit, a multivibrator circuit and a trigger, and the oscillating circuit is electrically connected with the trigger through the multivibrator circuit. The oscillating circuit comprises a first integrated circuit, a first resistor and a first capacitor, the model of the first integrated circuit is NE555, the sixth end of the first integrated circuit is electrically connected with the third end of the first integrated circuit through the first resistor, and the sixth end of the first integrated circuit is grounded through the first capacitor; a third end of the first integrated circuit is electrically connected with an input end of the multivibrator circuit, in the ultra-high-speed picosecond pulse rising edge generator, a high-frequency oscillation circuit is output through the oscillation circuit, frequency division oscillation output is carried out through the multivibrator circuit, and therefore picosecond-level oscillation output is achieved, and finally a pulse signal is output through the trigger. The whole circuit is simple in structure, high in practicability and high in cost performance.

The utility model provides an ignition pulse width adjustable MARX generator protection circuit, and belongs to the technical field of electric vacuum emission, the protection circuit comprises a sampling circuit, the sampling circuit comprises a current transformer and a sampling resistor R1, the current transformer is arranged between a high-voltage ignition signal generated by an MARX generator and a load, and the sampling resistor R1 is arranged on a secondary winding of the circuit transformer; the comparison circuit comprises a comparator, a first resistor R2 and a second resistor R3, the same-direction end of the comparator is connected with the current transformer, the reverse-direction end of the comparator is connected with a voltage division network formed by the first resistor and the second resistor, and the comparison circuit is used for comparing the sampling voltage of the high-voltage ignition signal with a set protection threshold voltage; the pulse width adjusting circuit comprises a monostable multivibrator, a third resistor and a capacitor, and the monostable multivibrator is grounded through a resistance-capacitance network formed by the capacitor and the third resistor; and the control circuit is connected with the pulse width adjusting circuit.

The invention relates to the technical field of control circuits, and discloses a multifunctional switching control circuit and method for a car lamp based on a 555 timer, and the circuit comprises a car lamp which comprises a 555 timer chip U5 which works in an astable multivibrator mode and outputs signals with different pulse frequencies, duty ratios and modes by receiving signals of a peripheral resistance-capacitance network, and the 555 timer chip U5 is used for switching the car lamp to the mode of the 555 timer chip U5; the function switching of the vehicle lamp is realized; one end of the resistor RA1 is connected with a power supply pin of the 555 timer chip U5; one end of the resistor RB1 is connected with the resistor RA1, and the other end of the resistor RB1 is connected with a threshold pin of the 555 timer chip U5; and one end of the capacitor C35 is connected with the resistor RA1 and the resistor RB1, and the other end of the capacitor C35 is grounded. According to the multifunctional switching control circuit and method for the vehicle lamp based on the 555 timer, the 555 timer chip which is low in cost and high in stability is adopted to replace a single chip microcomputer or a special integrated circuit in the prior art, the cost of the vehicle lamp control circuit is effectively reduced, and the economical efficiency of a low-cost vehicle type or a specific module is improved.

The present invention provides a method for detecting female pelvic floor muscle pressure, comprising the steps of (A) placing at least one thin film pressure sensor at an appropriate position in the body of a female user so that the pressure of the user's pelvic floor muscles can be transmitted to the thin film pressure sensor, wherein the thin film pressure sensor is electrically connected to a multivibrator, and the thin film pressure sensor forms a feedback resistor of the multivibrator, wherein the multivibrator is configured so that the oscillation frequency of the multivibrator corresponds to the pressure applied to the thin film pressure sensor; and (B) detecting the oscillation frequency of the multivibrator, and obtaining a pressure value applied to the thin film pressure sensor based on the corresponding relationship between the oscillation frequency of the multivibrator and the pressure applied to the thin film pressure sensor.

An electrical / electronic circuit for detecting the activation of a secondary access point for controlling or operating an electrical / electronic device, comprising a primary side (P) with a first potential, a secondary side (S) having the secondary access point with a second potential, wherein the second potential exists between two connecting lines, wherein the primary side (P) has an astable multivibrator with a comparator (K) having an impedance-dependent oscillation frequency of an alternating voltage generated by a voltage supply (V), characterized in that the secondary side (S) of the electrical / electronic circuit has a rectifier (G), in particular connected to the two connecting lines, wherein the rectifier (G) is connected in parallel to the primary side (P) with two lines, each connected to a Y-capacitor (C1, C2), in a galvanically isolated manner.wherein a capacitor (C3) is connected in parallel to the rectifier (G), the capacitor (C3) can be bypassed by an auxiliary switch (NS) of the auxiliary station which is to be influenced when actuated, so that when bypassed the resulting oscillation frequency of the astable flip-flop changes as an indicator of the actuation of the secondary access point.

A method (and corresponding apparatus) of analyzing the behavior of an electrochemical double layer (EDL) by replacing a classic capacitor in an astable multivibrator circuit with an electrochemical cell. By pushing the EDL into resonance, the induced charging and discharging of the double layer results in a square waveform output that has a characteristic frequency audible to the human ear. Variations in the electrolyte concentration and identity yield distinct frequencies. The method provides sensory insight into EDL rearrangement and behavior with an apparatus that is simple and robust. The apparatus allows the analysis of time-dependent EDL rearrangements occurring upon the application of a voltage. The apparatus provides insight, via an audible signal perceptible to the human ear, into the fundamental electrochemical principles governing chemical transformations.

The present invention relates to a magnetic resonance heating device comprising: a resonant circuit; a power switching circuit. The power switching circuit includes two switching channels capable of high frequency switching and operates on the principle of a push-pull oscillator circuit or a multivibrator circuit, when combined with the resonant circuit will stabilize the switching frequency at the resonant frequency of the resonant circuit to produce high power sources to supply for heating applications. The magnetic resonance heating device according to the present invention may be provided as a tin welding machine, a non-contact heating device, a heating equipment for a plastic production system, an instant water heater, an induction cooker, etc.

The present disclosure is a wound dressing material made of fabric, which accelerates the healing process of a wound to which it is locally applied, comprising an applicator (10) containing a square-wave-generating multivibrator electronic circuit (12), which is connected to the aforementioned spunbond fabric (11 ) to generate an electric field and exhibit a bactericidal effect and an effect preventing biofilm formation, the spunbond fabric (11) containing a multilayer film made of chitosan, and a control unit (20) supplying the applicator (10).

The application discloses a wireless infrared voice transmission system with adjustable carrier frequency and automatic calibration, which comprises a conference host, an infrared receiver, a microphone unit and a communication control module. A digital-analog hybrid FM modulation module modulates the voice signal collected by the microphone to an adjustable multiple resonant oscillator to obtain an FM modulated radio frequency signal, and the infrared driving module drives the infrared light carrying the voice signal to be emitted. The photoelectric conversion module converts the infrared light into a radio frequency electrical signal, and the multi-stage amplification driving module amplifies and automatically gains the radio frequency electrical signal and then controls the output of the RF signal to the conference host. The signal demodulation module restores the audio signal according to the RF signal and outputs the audio signal through the audio output driving module. The digital precise tuning of the digital-analog hybrid FM modulation and demodulation and the multiple resonant oscillator can eliminate the frequency deviation caused by temperature drift and device aging, ensure the 100Hz-20KHz full-band transmission bandwidth and maintain the group delay characteristics, and guarantee the gain stability and consistency of the multi-machine cascade.

The present invention discloses a control circuit for a temperature-compensated quartz tuning fork accelerometer. The present invention transforms the original internal temperature field of the quartz tuning fork accelerometer collected by a temperature sensor into a temperature compensation voltage. After fusing it with the original acceleration information detected by a multivibrator and an F / V converter through an adder, a frequency signal after temperature compensation is output through a V / F converter. The present invention can achieve comprehensive compensation for the zero offset and scale factor temperature coefficient of the quartz tuning fork accelerometer. The present invention can also adjust the zero offset and scale factor of the quartz tuning fork accelerometer by changing the conversion coefficients of the F / V converter, V / F converter, and adder. The present invention can be widely applied to military and civilian fields such as aircraft autonomous navigation, oil while drilling inclinometer systems, and microgravity field measurement, and has great economic and social benefits. The present invention can be applied to the control of other types of tuning fork accelerometers and has general applicability.

The utility model relates to a non-conductive or conductive liquid level detection device, a sensor and an electric appliance, and the device comprises a multivibrator driven by a direct-current power supply, and the multivibrator is provided with an oscillation / oscillation stopping control end and an oscillator signal output end. A metal liquid level sensing probe is connected to the oscillation / oscillation stopping control end; when the measured liquid level reaches or exceeds the height of the metal liquid level sensing probe, the multivibrator stops oscillating, and the signal output end of the oscillator outputs a high level or a low level; when the measured liquid level is lower than the height of the metal liquid level sensing probe, the multivibrator performs self-oscillation, the signal output end of the oscillator outputs an astable pulse oscillation signal, and the height position of the liquid level is recognized according to the output state. The liquid level detection device can effectively and accurately detect the liquid levels of liquids with different electrical conductivity water qualities, even can detect the liquid level of liquid grease, and particularly can detect non-conductive pure water and distilled water.

The invention discloses a wireless infrared voice transmission system with adjustable carrier frequency and automatic calibration, which is provided with a conference host, an infrared receiver, a microphone unit and a communication control module, and is characterized in that a digital-analog hybrid FM modulation module modulates a voice signal acquired by a microphone to an adjustable multivibrator to obtain an FM modulated radio frequency signal; the infrared driving module is used for driving to emit infrared light carrying voice signals; the photoelectric conversion module converts the infrared light into a radio frequency electric signal, the multi-stage amplification driving module amplifies and automatically gains the radio frequency electric signal and then controls to output an RF signal to the conference host, and the signal demodulation module recovers an audio signal according to the RF signal and outputs the audio signal through the audio output driving module. By adopting digital-analog hybrid FM modulation and demodulation and digital precise tuning of the multivibrator, frequency offset caused by temperature drift and device aging can be eliminated, the 100Hz-20KHz full-band transmission bandwidth is ensured, the group delay characteristic is kept, and the gain stability and consistency of multi-machine cascade are ensured.

The present invention discloses a method and circuit for measuring the peak value of partial discharge based on a single chip microcomputer, which belongs to the field of partial discharge detection and diagnosis of power equipment. The method uses a first operational amplifier unit to collect the partial discharge signal, and its inverting input terminal receives the output signal of the second operational amplifier unit. The voltage V1 of the output signal of the first operational amplifier unit is compared with the noise voltage V ref , if V1 is greater than V ref , then the first operational amplifier unit and the energy storage capacitor are turned on, and the voltage V1 and the voltage V2 of the output signal of the second operational amplifier unit are further compared. If V1 is greater than V2, the energy storage capacitor is charged, otherwise the energy storage capacitor maintains the voltage V2. When V2 is greater than the reference voltage V DAC When increasing V DAC Otherwise, the monostable multivibrator unit generates an excitation pulse, which controls the second analog switch to discharge the energy storage capacitor and output V DAC The present invention realizes accurate peak value capture of partial discharge signal through progressive comparison and is applicable to monitoring of high voltage equipment.

The present invention provides a circuit and an automotive test method for simulating the signal of a two-wire Hall sensor, including a multivibrator circuit that starts oscillating when the circuit is powered on and outputs a PWM signal, and the PWM signal is used to simulate the signal of the two-wire Hall sensor; it also includes a duty cycle adjustment circuit and a constant current modulation circuit to adjust the duty cycle of the PWM signal so that the output current is stabilized at a certain current value to form a constant current. By adopting a pure circuit simulation method, the present invention adjusts the output frequency, duty cycle, and output current of the circuit according to requirements, realizing the function of simulating the signal of the two-wire Hall sensor. The present invention is used to replace the two-wire Hall sensor during the development process of automotive controllers for design verification and testing, effectively reducing the development cost. The present invention is safe and reliable, simple to operate, highly practical, compresses the development cycle of the controller, improves the development efficiency, and completely covers the test requirements.

The invention belongs to the field of analog integrated circuit design, and particularly relates to a differential cross-coupled multivibrator, which comprises an oscillation main circuit used for generating periodic rectangular waves; the control voltage selection circuit is used for realizing frequency adjustment of the oscillation main circuit by selecting a control voltage; the control voltage buffer circuit is used for suppressing power supply noise interference in the oscillation main circuit and assisting the control voltage selection circuit to realize frequency adjustment; by introducing the control voltage selection circuit, the frequency of the oscillator can be changed along with the change of the voltage, so that the effect of the voltage-controlled oscillator is realized; a control voltage buffer circuit is introduced to reduce power supply noise and reduce the influence of process deviation.

The invention relates to a 180-degree phase shifting method and a phase shifting circuit, which are characterized in that external delay resistors and delay capacitors of two monostable multivibrators are set, so that the pulse widths output by the two monostable multivibrators are half of the switching period of an input PWM1 (Pulse Width Modulation 1); then, the connection relation of the two monostable multivibrators is set up, so that the first monostable multivibrator triggers PWM wave output at the rising edge of the input signal PWM1, the second monostable multivibrator triggers PWM wave output at the falling edge of the input signal PWM1, and duty ratio information of the input signal PWM1 is invisibly obtained through the triggering mode; and a trigger is designed to reversely extract the duty ratio signal, so that a PWM2 signal which is subjected to 180-degree phase shift and corresponds to the PWM1 signal with the input duty ratio of 0.5-1 can be obtained. 180-degree PWM wave phase shift can be realized by adopting two chips and two groups of resistors and capacitors, the circuit is simple to realize, and an economic scheme for phase shift control is provided for a PWM controller type switching power supply.

The invention discloses a tramcar auxiliary release solenoid valve driving protection system which is realized through a pure hardware circuit and comprises an instruction pulse generation circuit, a single power-on limiting circuit, a blocking time timing circuit, a two-input AND gate and a driving module. The single-time power-on limiting circuit and the blocking time timing circuit respectively utilize a monostable multivibrator, a resistor and a capacitor combination to set the single-time power-on time and the forced rest time of the electromagnetic valve. The two-input AND gate is used for controlling logic processing of signals, ensuring that a new instruction is shielded in a blocking period, and preventing repeated triggering. The driving module controls on-off of a relay through a triode so as to control on-off of an electromagnetic valve. The system is simple and clear in structure and easy to implement and maintain, the reliability and safety of the braking system are remarkably improved, the overheating problem caused by too long continuous working time or too short repeated starting interval is effectively avoided, the system failure rate is reduced, and the vehicle operation efficiency is improved.

Flashing lamp circuit (10; 110) comprising: a light source (18; 118), a multivibrator (14; 114) suitable for connection to a power supply (12; 112), and a switch / regulator circuit (16; 116) operationally connected between the multivibrator (14; 114) and the light source (18; 118), the switch / regulator circuit (16; 116) comprising: a first transistor (Q4) comprising a gate, a source, and a drain terminal, the source terminal of the first transistor (Q4) being connected to the light source (18; 118); a resistor (R12) connected between the drain terminal of the first transistor (Q4) and ground; a diode (D2) connected between the gate terminal of the first transistor (Q4) and the multivibrator (14; 114) is connected;and a second transistor (Q3) comprising a base, a collector and an emitter, wherein the collector of the second transistor (Q3) is connected to the gate terminal of the first transistor (Q4), the base of the second transistor (Q3) is connected to the drain terminal of the first transistor (Q4), and the emitter of the second transistor (Q3) is connected to ground, wherein the first transistor (Q4) acts as an amplifier switch between the multivibrator (14; 114) and the light source (18; 118), and wherein the first transistor (Q4) further acts as a constant current regulator between the multivibrator (14; 114) and the light source (18; 118).

The invention discloses a simple digital width modulation narrow pulse generation circuit, and relates to the technical field of electronic circuits. The circuit comprises a multivibrator, an RC series-parallel network, a digital adjustable stabilized voltage supply and a comparator. The multivibrator is composed of an NAND gate 1 and an NAND gate 2, outputs a rectangular wave signal to drive an RC series-parallel network, and generates a pinnacle pulse waveform on a resistor R3; the adjustable voltage-stabilized power supply is designed based on TL431, outputs adjustable stable voltage by controlling a binary resistance network, and is connected with the anti-phase end of the comparator; the in-phase end of the comparator receives a pinnacle pulse signal, and outputs a width-adjustable narrow pulse through dynamic threshold comparison. Through combination of RC charging and discharging characteristics and an adjustable threshold value, digital controllable adjustment of the pulse width from 30 ns to 660 ns is realized, and the circuit is simple in structure, low in cost and high in anti-interference performance.

The application discloses an IGBT junction temperature online monitoring circuit based on gate voltage falling time, comprising a high-speed comparison unit, a pulse gating unit and a signal conversion unit; the high-speed comparison unit comprises an isolated input operational amplifier, a high-bit comparison unit, a low-bit comparison unit, input reference units CMPA and CMPB and a logic XOR gate unit; the pulse gating unit comprises a high-speed precision monostable multivibrator unit and a high-speed MOSFET gating unit; and the signal conversion unit comprises a diode clamped second-order RC low-pass detection unit and an isolated output operational amplifier. The falling time is taken as a temperature-sensitive electrical parameter to realize the junction temperature online monitoring of the IGBT, and the application is simple and easy to realize, has high linearity, small volume, low cost and high precision when applied to online monitoring, and has no influence on the main circuit.

The invention discloses a capacitance measurement system and method based on the Internet of Things, and relates to the technical field of capacitance measurement, and the system comprises an oscillator module, a single-chip microcomputer module, a display module and a communication module. The multivibrator is used for converting a capacitance value to be measured of the capacitor to be measured into a square wave signal with a corresponding frequency; the single chip microcomputer module is used for acquiring the square wave signal, determining a square wave frequency value corresponding to the square wave signal by adopting an adaptive frequency-capacitance conversion algorithm, and performing capacitance calculation according to the square wave frequency value to obtain a capacitance measurement result corresponding to the capacitor to be measured; the display module is used for displaying the capacitance measurement result in real time; and the communication module is used for transmitting the capacitance measurement result to the upper computer to realize an Internet of Things function. According to the invention, the accuracy and stability of capacitance measurement can be improved while the function of the Internet of Things is realized.

The invention discloses a simple width-adjustable narrow pulse generation circuit, and relates to the technical field of electronic circuits. The circuit comprises a multivibrator, an RC series-parallel network, an adjustable stabilized power supply and a comparator. The multivibrator is composed of an NAND gate 1 and an NAND gate 2, outputs a rectangular wave signal to drive an RC series-parallel network, and generates a pinnacle pulse waveform on a resistor R3; the adjustable voltage-stabilized power supply is designed based on TL431, and reference voltage is changed by adjusting an adjustable resistor R5 and input to the anti-phase end of the comparator. The in-phase end of the comparator receives a pinnacle pulse signal, and outputs a width-adjustable narrow pulse through dynamic threshold comparison. Through combination of RC charging and discharging characteristics and an adjustable threshold value, continuous adjustment of the pulse width from 40ns to 660ns is realized, and the circuit is simple in structure, low in cost and high in anti-interference performance.

The present invention provides a multi-channel timer circuit device and system, which relates to the field of electronic circuit technology. The device comprises: a processor utilizing a field programmable logic array (FPGA) for performing timing logic control and intelligent pulse signal processing; a signal input circuit for synchronizing the clock, setting target times for each load in the multi-channel timer, and transmitting the target times to the processor; and a reference clock circuit for calculating the timing of each load. Specifically, the circuit utilizes a superconducting quantum interference multivibrator (SQIM) to generate reference pulses, which are then timed using an adaptive frequency divider to obtain the timing. The present invention utilizes a field programmable logic array (FPGA) processor and a SQIM, combined with adaptive frequency division coefficients, temperature, and noise compensation algorithms, to achieve high-precision timing, addressing the low precision of traditional timers and meeting the requirements of industrial automation scenarios.

The invention discloses a partial discharge peak value measuring method and measuring circuit based on a single-chip microcomputer, and belongs to the field of partial discharge detection and diagnosis of power equipment. According to the method, a first operational amplifier unit is adopted to collect partial discharge signals, and an inverted input end receives output signals of a second operational amplifier unit. The voltage V1 of the output signal of the first operational amplifier unit is compared with the noise voltage Vref, if V1 is larger than Vref, the first operational amplifier unit and the energy storage capacitor are conducted, V1 is further compared with the voltage V2 of the output signal of the second operational amplifier unit, if V1 is larger than V2, the energy storage capacitor is charged, and otherwise, the voltage V2 is kept by the energy storage capacitor. When V2 is larger than reference voltage VDAC, VDAC is progressively increased and stored, otherwise, the monostable multivibrator unit generates an excitation pulse, the excitation pulse controls the second analog switch to enable the energy storage capacitor to discharge, VDAC is output, and peak voltage of the partial discharge signal is calculated. Accurate peak capture of the partial discharge signal is realized through progressive comparison, and the method is applicable to monitoring of high-voltage equipment.

The utility model relates to a score indicator device based on 555 timers and counters. The score indicator device comprises two 555 timer circuits, a logic OR gate, a logic NAND gate, a JK trigger 2-bit carry counter circuit and a seven-segment cathode nixie tube. The 555 timer circuit generates an unsteady waveform with controllable duration and generates a continuous square wave signal with controllable frequency and duty ratio, the square wave signal is input into the JK trigger 2-bit carry counter circuit after being operated by the logic AND gate, the signal is reset and carried by the logic circuit, the signal is input into the decoder chip, and the decoder chip is connected with the 555 timer circuit and the JK trigger 2-bit carry counter circuit. And finally, corresponding numbers are displayed by the seven sections of cathode nixie tubes. According to the utility model, two basic applications of the 555 timer, a simple chip and a nixie tube are utilized to complete the function of the score indicator, and the purpose of recording different scores by the score indicator is achieved by selecting the resistance values of the external parallel resistors of the monostable multivibrator circuit.

The utility model provides a dual-channel digital frequency meter, and belongs to the technical field of digital frequency meters. Comprising a single-chip microcomputer, a display circuit and a power supply circuit used for supplying power, the system also comprises a first signal shaping circuit, a first relay switch K1, a first frequency divider circuit, a second relay switch K2, a second signal shaping circuit, a third relay switch K3, a second frequency divider circuit, a fourth relay switch K4, a multivibrator circuit used for outputting a preset gate signal, and a gate control circuit. According to the dual-channel digital frequency meter, dual-channel measurement can be achieved, two paths of signals can be measured and compared at the same time, and the requirement for simultaneous detection and analysis of different signals in more complex scenes is met.

The utility model discloses a high-low level alternating output circuit with a timing adjustable function. The high-low level alternating output circuit comprises a multivibrator circuit, a counter group, a zero clearing signal circuit and a JK trigger group, wherein the multivibrator circuit is used for generating a pulse clock signal, and the output end of the multivibrator circuit is connected to the counter group; the counter group is used for timing output of high and low levels, the output end of the counter group is connected to the reset signal circuit, and the output end of the reset signal circuit is connected to the JK trigger group and used for driving the JK trigger group to trigger and output high and low level signals in a set time period. The utility model has the advantages that the timing output of multiple paths of high and low levels is realized through the digital circuit, and the circuit is simple and reliable. Multi-path timing output can be realized, the timing time is adjustable, and high and low levels can be circularly output.

A novel control device and method for widening input voltage range, the device comprising a transformer TD, an error amplifier EAP1, an error amplifier EAP2, a PI regulator PI1, a PI regulator PI2, a variable frequency sawtooth wave generator SAW, a comparator CMP, an inverter NOT, a multiplier AND1, a multiplier AND2, a drive circuit DR1, a drive circuit DR2 and a monostable multivibrator generator MONO, and the control method adjusts the output voltage by simultaneously adjusting the working frequency and the duty cycle. Through the implementation of the application, the input voltage range of the double-output LLC resonant converter is widened, the working frequency and the duty cycle can be changed simultaneously during operation, and after the input voltage jumps or the output branch load jumps, the working frequency of the control method is closer to the resonant frequency compared with the working frequency of the variable frequency control.

The invention relates to a non-conductive or conductive liquid level detection method, a detection device and an electric appliance, and the method comprises the steps: firstly, manufacturing a multivibrator driven by a direct-current power supply, and arranging an oscillation / oscillation stopping control end and an oscillator signal output end on the multivibrator, a metal liquid level sensing probe is connected to the oscillation / oscillation stopping control end, when the measured liquid level reaches or exceeds the height of the metal liquid level sensing probe, the multivibrator stops oscillation, and the signal output end of the oscillator outputs a high level or a low level; when the measured liquid level is lower than the height of the metal liquid level sensing probe, the multivibrator performs self-oscillation, the signal output end of the oscillator outputs an astable pulse oscillation signal, and the height position of the liquid level is recognized according to the output state. The liquid level detection device can effectively and accurately detect the liquid levels of liquids with different conductivity water qualities, even can detect the liquid level of liquid grease, and especially can detect non-conductive pure water and distilled water.

A wavelength interrogation apparatus includes an optical fiber with a fiber core and an interference pattern in the fiber core, one or more photodiodes or photo-sensors to convert from a transmittance light of the optical fiber to an electrical signal, and an electrical circuit to generate a pulse with a predetermined duration, wherein the apparatus provides image acquisition at accurate start wavelength. The electrical circuit can include a first amplifier, a first differentiator or high-pass filter, a comparator, and a multivibrator, and can include other components.