论文部分内容阅读
故障现象:一台环宇47C—2型彩电,开机后有“吱吱”声,无光栅。检修过程:根据故障现象判断故障在开关电源或行输出电路。开机后实测开关电源的输出电压只有37V。断开行负载并在电源输出端接入50W电烙铁,测开关电源输出电压为109V,恢复正常。说明故障的原因是行电流过大。关机后在线检测行管c极到地的直流电阻值,正反向分别为600Ω和2.7kΩ。试将行推动变压器次级
Symptoms: a Universal 47C-2 color TV, boot, “creak” sound, no grating. Maintenance process: According to the fault phenomenon to determine the fault in the switching power supply or line output circuit. Measured after switching on the power switch output voltage is only 37V. Disconnect the line load and access the power output of 50W electric iron, measuring the power switch output voltage of 109V, back to normal. The reason for the failure is that the line current is too large. On-line monitoring after the shutdown line c very DC resistance, the positive and negative were 600Ω and 2.7kΩ. Try to promote the transformer secondary