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本文主要介绍渴望HCD139(38)P/TSDL 多功能全制式来电显示电话机的故障检修。⒈不能振铃可以通过在振铃状态测量C7 滤波电容两端电压来判断故障在振铃输入电路还是振铃输出电路或U1 微处理芯片存在不良。如果C7 两端有27V 左右的电压,说明故障在振铃输出电路或U 1 微处理芯片;
This article describes the eager HCD139 (38) P / TSDL multi-standard full-line caller ID telephone troubleshooting. ⒈ can not ring You can ring the state by measuring the voltage across the C7 filter capacitor to determine the fault in the ringing input circuit or ringing output circuit or U1 micro-chip poor. If the C7 has a voltage of about 27V across the ends, indicating that the fault is on the ringing output circuit or the U1 microprocessor chip;