遥控器的维修

遥控器的维修 Remote control (2007-11-056:04) tags: knowledge/exploration There are various kinds of color TV remote controls, but the basic principle is the same. But under the control of the remote control, the keyboard signal is processed in a series of processing in the integrated block, which is converted into a red light signal. The remote controls are most likely to be damaged by a fall and a relatively small circuit failure. In the case of repair, the remote control unit should be replaced by the same type of device, and the tube and infrared transmitter can find the replacement device which is approximately suitable. For example, there are more C1815 in the market, the S8050 pipe can replace the NPN type, and the CD9012 tube can replace the PNP drive tube. The infrared spectrum of remote infrared transmitting tube is about 950mm, and the emission power is not very large, except for the individual case, the normal color remote transmitting tube can be replaced with each other. Most remote controls have a low frequency of oscillation crystals, which can be used in a similar way. This paper elaborates the methods of inspection and judgement, and the remote control damage common types and maintenance instances: (1) the inspection methods of the remote control 1, alternate method: the remote control is aimed at the control function of the same model color TV to do the experiment, if the same doesn't work, show the fault is in the remote control itself; Or use the same model remote control to experiment with the existing color TV, if can normal remote control motion, explain the failure is in the original remote control itself. This method is easiest and reliable. 2, radio method: find a transistor radio, around 455-650 KHZ frequency will be dispatched to the mw (preferably in the absence of radio frequency position), aim the remote control is close to zero on the radio. 3 meters, press the next key, the radio "da" sound; Repeat button, then heard "da" and "da" and "da" sound, oscillation and keyboard remote control circuit is normal, but can not show the stand or fall of infrared transmitting tube. If there is no such thing as pressing the key, it indicates that the remote control is not working properly. Measurement: when the remote control is pressed, the signal output voltage of the receiver is 0. 1-0. 3 v. Or the remote signal input voltage range of the CPU chip in the machine is 0. 25 to 0. 4V, which indicates that the receiving and firing is basically normal work. 4, the current method: although the use of integrated circuit has a variety of remote control model, but its working current size close, we can measure the working current of the remote control, quick to judge the malfunction. The static current of the remote control should be less than 1 microampere, and individual models should be less than 3 microamps. The dynamic current of the press key should be in the 4-8ma, the remote control of the indicator lamp, the indicator current about 2mA according to the current size, the fault area, the specific situation is as follows: (1) the remote control is too large A, if the static and dynamic current is 10mA, the circuit board keys are transmitted and short-circuited. The static current is normal when the current is current, but the static current of the dynamic current and the release of the current is 25mA, which indicates that the oscillating capacitance is open, or the capacitance is less than 2PF. C, the static current is normal when the electricity is current, but the dynamic current and the static electric current after release are 65mA, which indicates that the vibration-vibration deteriorates and the frequency increases too much (2) the dynamic current is too small A, if the static current and dynamic current are 180 microamps, it indicates that the vibration is open The dynamic current is 200 microampere, which indicates the diode is damaged C, the dynamic current is 150 microampere, indicates that the power filter capacitor opens or the capacity decreases D, a dynamic current of 200 microampere, indicates that some circuits within the integration block fail E, the dynamic current is 2mA, which indicates that the battery is obviously low F, the dynamic current is 1. The change between 5-3ma indicates that the battery spring is rusted and the voltage is 2-2. 5 v change The above method to comprehensive use, it is worth noting that the radio method, current method, measurement method can't 100% sure to identify and judgment come to the conclusion that, because of wrong encoding, deviation and so on also creates the illusion. (2) the remote control damages common types and causes According to the records of years of maintenance, The common type of remote control is now damaged, and the reason for this is as follows: A, vibration-de-welding or bad, the reason is A break, the component itself is not good. B, the remote control circuit board split or the conductive film fracture, the reason is to use improper fall break, the element is resistant to the vibration difference. C, battery leakage corrosion contact and circuit board, because the battery is not replaced in time. D, the resistance of the conductive rubber has been increased due to the poor use of the environment and the defective elements. The E, the battery and the spring clamp are not in touch, the reason is to use long and often vibration to make the elasticity to be poor and rusty. F, emitting diodes are bad, or unsoldering, because the elements themselves are bad, the performance is poor, the vibration. G, chips or transistors are bad because the elements themselves are bad and the performance is poor. H, resistance capacitance is bad, because the component itself is bad and the performance is poor. (3) maintenance instances Example 1. The good thing is bad when the remote function is good. Sometimes it can be used with a few strokes. After disassembling the shell, examine the failure to find the virtual solder, and shake with a slight noise in the vibration. The reason for the failure is that the inner crystal is loose and the contact is bad. The kangjia Y60 remote control has only a few keys, and other keys fail. This is after many remote control using long will send failure, the reason is that the rubber foam on the keyboard and the dust stick in the circuit on contact, conductive rubber and the contact point contact undesirable. If you clean the circuit, you can troubleshoot it. Example 3, the long rainbow 2588A color TV remote control is only valid for one meter range. This is because there is a problem with amplifying circuits or transmitting tubes. Check the push pipe and the emission diode, find the emission diode internal resistance obviously increased, and then the remote control is increased to about 8m. The remote control of the C1462 color TV is serious The new battery is only three days away, and the normal remote control is small when it is not pressed, and the battery can be used for about a year and a half. Electricity is serious fault components caused by the leakage, should focus on inspection with battery tube V1401 C1403 filter capacitance shunting and promoted and fault in order to promote this column tube leakage, by substituting S8050 BC338 tube, troubleshooting. The Hitachi CPT -2125sf is manual, and remote control is out of control. Because there is no good remote control and color TV at hand, it is impossible to judge by alternate method. Using the radio method and current method to show that all normal, using the measuring method, the signal amplification of the receiving window chip IC1201 in the color machine amplifies the output of the output terminal 7 with a voltage of 1. 6 v. In 1 and pointer. 4 v - 1. 8V range change (when pressing any key), the remote signal input terminal 15 for the cpus, TC1101, is 0. 4V, and the pointer is 0. 25 to 0. 6V range changes (when pressed by the next one), these are normal phenomena. The CPU is suspected, but the CPU cannot be ruled out. Will others intact after the remote control (CLE - 862 - g) borrowed, normal control, thus determine the remote control has fault, due to the remote control in addition to the chip UPD1943G did not change, other components are changed, so the judgment of this fault is the remote control chip encoding confusion caused, when maintenance should be paid attention to this point, little detours.