FH-408型自动定标器是使用较广的一种仪器;通常情况下不易出现故障,但在较恶劣的环境,如我国南方的春季和夏初,湿度很大,仪器较易出毛病。除某些晶体管可能发生损坏外,高压变压器的层间绝缘变差或短路也是较常见的故障。在后者情况下表现为高压输出降低或无高压,使仪器不能正常工作。由于变压器不象其它元件能在市面上买到,给维修工作带来一些不便。我们根据长期使用经验,采取预防措施,把高压变压 FH-408 automatic scaler is a widely used instrument; it is not prone to failure under normal circumstances. However, in harsher environments such as spring and early summer in southern China, the humidity is very high and the instrument is prone to failure. In addition to some transistors may be damaged, the high voltage transformer insulation interlayer insulation or short circuit is also a more common fault. In the latter case, the high pressure output is reduced or no high pressure, so that the instrument does not work properly. Since transformers are not commercially available like other components, there are some inconveniences to maintenance work. We based on long-term use of experience, take precautions, the high-pressure transformer