0 the introduction of magnetographers, due to their relatively simple structure, speed of detection, low cost and low environmental pollution, has been widely used in the air, machinery, cars, internal combustion engines, railways, ship berths, etc. Because of the magnetic instability of certain fluorescent magnetographers on wheels, the controlled silicon voltage programme in the eccentric circuit control system needs to be improved. At present, of the magnetic powder detection equipment used in production, weekly more than two controlled silicones are used to reverse the current and to form a voltage circuit. And this gives us a way to use the tca 785 switch trigger to achieve voltage for a controlled silicon. 1 controlled silicon voltage principles and triggers have the advantage of small size, light weight, high stress tolerance, low price, control sensitivity and long useful life, which allows applications of semiconductor devices to move from the weak to the strong field of electricity and to be widely used in large power electronic circuits such as currents, reverses and voltage. Controlled silicon is an active switch device that is kept in a non-conductive state until a smaller control signal triggers (or “fire”) to it, and, once activated, even when the trigger is withdrawn, it maintains the guidance and, in order for it to be disabled, either by adding a reverse voltage between its anode and cathode or by reducing the flow of the controlled silicon diode to below a certain threshold. The magnetic circuits of the magnetographer are in no way controlled by silica to control the weekly magnetic current. 1. 1 controlled silicon-repressible conductivity and disconnection are achieved when the anode level is higher than the cathode level and there is sufficient control over positive voltage and currents, while the anode level is higher than the cathode level and the anode current is greater than the maintenance of currents, the conductivity of a controlled silicon is maintained: in the anode, when the level of electricity is below the cathode level or the current of the anode is smaller than when the current is maintained, the controlled silicon changes from a conductive state to a shutdown. Generating a trigger pulse is one of the conditions necessary for controlled silicon guidance, the mass of which will directly affect the performance and performance of the controlled silicon. Thus, the reliability of the trigger circuit, which produces the trigger signal, is directly related to the mass of the controllable silicon voltage device. 1. 2 controlled silicon is triggered by a controlled silicon for communication regulation, usually by two triggers, i. E., excessive zero trigger and transfer trigger. The over-zero trigger is the trigger of the transistor conduit near the zero point of the power voltage and the current exchange of voltage by changing the weekly frequency of the transistor catheter during the set period. Controlled silicon cycles are zero-triggered workwaves as shown in figure i. Figure 1 shows tc for the control period of the signal, t1 and t2, respectively, the controllable silica pass time, and tc=t1+t2. The circuit is adjusted for voltage by changing the break time of a controlled silicon, that is, by changing the number of weekly waves. Usually, the control circuits directly connect the load with the input voltage u at tc and then break t2 seconds, i. E. Adjust the load's output by changing the break time. The transfer triggers the voltage by changing the channel angle. Figure 2 shows the conductivity at 45, 90 and 135° of the transport trigger, respectively, when the pulse is triggered. Figure 2 shows that the voltage at both ends of the load varies with the movement trigger. The transfer triggers a break in every controllable silicon period, either positive or negative, i. E., the output is continuously adjustable, so it adapts to loads, but during the control process it causes electromagnetic interference with the grid. Depending on the nature of the load, the conditions of use and the surrounding environment, this design selects the transfer phase trigger as the trigger control for controlled silicon. 2 the design of the controllable silicon transfer trigger circuit has been widely applied as the integrated circuit making technology has improved, and the integrated trigger has overcome the shortcomings of the separate element trigger. This paper uses integrated trigger circuit tca 785 to modify existing equipment to improve its performance. 2. 1 the tca785 transverse trigger is a single transverse 785 transposition trigger, a two-bar direct interpolation of 16 feet of large-scale integrated circuits, which, compared to other chips, has the advantage of having a good output pulse alignment, a wide shift range, a wide and man-made output pulse, and thus a wider application. 2. The principles of tca785 work are shown in figure 3, where foot 11 transects control electrical level v11, foot 6 transmutation signals, foot 5 synchronized signals, foot 12 through the electrical surface, foot 9 and 10 by the sawn-tooth slope resistance and the electrical capacity, and feet 15 and 14 are pulse output q1 and q2 respectively. Synchronized voltage vsync is stored by the zd when zd detects its zero point, and is charged by the sr for control of the sawntooth generator rg, rg c10 by the constant flow source sc as determined by the resistor r9, and a pulse is generated by a pulse signal to the output logic unit when the sawn port voltage voltage voltage of c10 is greater than the transfer control voltage v11. As you can see, the pulsation phase triggers the pulse, which is controlled by the transfer control voltage v11, triggers the pulse, q1, q2 can be moved at 0° ~180°, and tube foot 14, 15
