In the process of counting and timing, the principle of PSM modulator in short wave transmitter has become a widely accepted form. In the 100KW PSM modulator for multiple overload counts of the controller, thermostatic element the working principle of the timing circuit and its main working circuit are monitored and protected according to the corresponding analysis data, so as to ensure normal operation.
In view of these problems, the article makes some brief analysis. The HF transmitter of DF100KWPSM, in order to prevent the failure and damage of components in operation, adopts a variety of detection and maintenance means to carry out corresponding measures to maintain, so as to ensure that in a series of modifications, we complete the maintenance and construction work.
In the process of rectification, DF100KWPSM carries out wave frequency detection, and carries out comprehensive statistics for the reciprocal value. In this way, while completing the original modulation task, it also carries out fault detection and maintenance work, so as to make the modulation overload counting statistics for the signal. In the analysis of the whole circuit, the overload calculation of the PSM modulation controller device is carried out several times, mainly through the basic circuit to adjust and control, as shown in Figure 1.
In Fig. 1, the single-pole double-hold switch S1 is a high-voltage switch which is automatically switched off. When the load exceeds three times in the process, the switch should be switched to the contact position No. 3, so as to ensure the safety of the whole operation. When the voltage U30 corresponds to the electrode at position 3 in the configuration process, the integrated voltage between U31A and U31B should also be allocated, so that the voltage and current stabilization can also be completed in the work of the timer. For the task of DF100KWPSM, the logic level is detected by the edge of the detector, and then analyzed.
The specific operation is not shown in Table L. In the process of load fault protection, if the load of the machine is too large, the signal Y in the whole control circuit will cause the corresponding clock signal to appear in the port CPO input to U30 when the low-voltage pulse of 0.5S is applied.
While doing this operation, it will also cause some slight disturbance of the low voltage pulse of QB at the port of B input U31A, which will generally maintain about 100S. As shown in Table 1, in the low-level input of voltage U30 at ports 13 # and 15 #, because the RESET value is zero, the count of port 100S is valid. In the power output of U31A, because it is contrary to AQ, and because it is high level, it may lead to overload in Y signal recovery.
Edge detector is mainly composed of four quadrant non-gates for U32, in which the input signal mainly comes from the 10_port of U27. In the work detection, the selection of high level and low level can be carried out. In the process of high power switching and low power switching, when the output pulse of edge detector is negative, the pulse width is 1500s, which makes the value of U31B appear Delta B= Delta QB=U31A. These data show that Delta CT2=0 as a whole, and according to the settings of timing U31B, we can also analyze the sustainability of 0.
22s in zero signal. When the high-level signal drives U30 to zero, the main reason is the reset function of RESET after 100 seconds. At this time, the negative pulse output of edge detector may be adjusted according to the monopolar trigger because of the delay effect, so as to ensure the normal operation in the work. In high-level processing, because the U28A signal will be adjusted from 1 # to 2 # in high-power to low-power operation, if the overload value occurs three times in this operation, the corresponding disconnection may occur, which will result in the display of 0 value on the edge detector.
In this way, the security of the whole work is protected. If the power is not able to be adjusted in time when the high voltage switch is low, the corresponding value of the panel will also fluctuate. As the value of the high voltage disconnect becomes Q2=Q3=1, and basically remains the same, if the low voltage power has three overload at this time, it will cause the overall edge detector output to be lower than the normal low level pulse.
Thus, it can not accurately reflect the precise problems in the circuit, and the panel display can only automatically zero.
In this series of improvements, if the internal problems of the unit may lead to some unnecessary troubles, manual reset processing is needed at this time. In the manual reset work, RESET should also be checked, so as to ensure that the corresponding trigger correction and conditioning, to ensure the orderly conduct of the whole work. In the process of manual reset, problems should be checked according to the corresponding regulations, and signals should be controlled by observing the specific indicators of Q2, Q3, Q4 and Q5, so as to complete the task. In the modulation control of short wave transmitter, the performance of the airframe is strictly required because of the constant transformation of high voltage and low voltage.
In order to ensure its overall safety performance, in the corresponding protection, three basic measures are more prominent: the failure prediction and analysis of transmitter, the hot backup protection of host computer and the interlocking protection of antenna.
DF100KWPSM can be used in routine broadcasting, because it can protect the modulation controller from overload counting, and has a certain application range in the detection of faulty components. In daily work, because all kinds of unavoidable faults may lead to the damage of components, so PSM technology appears to have a certain foundation in the industry. In the promotion of PSM, the downtime probability of transmitter is greatly reduced, which also shows that the effect of PSM in practical application is quite good.