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- Low Frequency Direction Finder 低频测向仪
- very high frequency direction finder 甚高频测向器
- medium frequency direction finder station 中频测向站
- High and Very High Frequency Direction Finder 高频和甚高频定向仪
- Medium and Very High Frequency Direction Finder 中频与甚高频测向器
- medium frequency direction finder 中频测向器
- Medium High Frequency Direction Finder 中高频测向器
- Ultra High Frequency Direction Finder 特高频测向仪
- The first of the British advantage was the development of High Frequency Direction Finders (HD/DF or “huff duff”) for shipboard use. 英国首先的优势是装备在甲板侧弦的高频方向定位仪（HD/DF）。
- Laser direct writing of micro-OVD with low frequency templates[J]. 引用该论文 魏国军;周小红;周雷;陈林森.
- The direction of the low frequency current with maximum frequency was also WSW. 低频流出现频率最多的方向和潮流基本一致。
- In electronics, undesirable low frequency currents interfering with a desired signal, and usually caused by a poorly screened alternating mains supply. 在电子学领域，一种不希望发生的低频电流，它干扰所要求的信号。通常这种现象是由于交流供电线路屏蔽不良引起的。
- high frequency direction finder 高频方向测定仪
- I am calibrating radio direction finder or adjusting compasses. 我正在校准无线电测向仪或校正指南针.
- The abnormal colours of seedlings turned a low frequency. 颜色异常的苗木出现频率较低。
- He has designed more than 30 types of safety equipments, including a low cost earthquake alarm, an epicenter direction finder and an epicenter distance locator. 他已经设计了30多种安全装置，包括一个低成本的地震报警仪，一个震中方向确定议，以及一个震中距离确定仪。
- Low Frequency Direction Finding 低频测向
- Inspection installation for loop antenna of direction finder on berth. 测向仪环状天线船台安装检查。
- If it is a low frequency sound, it is processed as an analog signal. 对低频声进行传统的处理。
- This effect is obvious at lower frequency band. 这种效应在振动低频区段更为显著。
