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一种易于产品化的十进制频率合成器
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作者 高泽溪 王诞 燕高成 《电子技术应用》 北大核心 1997年第12期34-35,共2页
介绍的频率合成器是用一个5MHz的恒温控制的高稳定时钟合成出2.7~3.6MHz十个标准子钟源,通过八个十进制电子开关一一加到八个(根据频率分辨率的要求可增减)混频环中,再经过倍频和混频可获得0.1Hz~100MHz... 介绍的频率合成器是用一个5MHz的恒温控制的高稳定时钟合成出2.7~3.6MHz十个标准子钟源,通过八个十进制电子开关一一加到八个(根据频率分辨率的要求可增减)混频环中,再经过倍频和混频可获得0.1Hz~100MHz频率范围的精密信号。由于十个子钟源及八个混频环,电路结构一样,器件品种相同,很容易产品化。 展开更多
关键词 频率合成器 频率分辨率 混频 倍频环
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一种做为计算机接口的字符叠加器电路
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作者 冯超英 朱敬东 《无线电工程》 1999年第4期41-42,64,共3页
字符叠加器是在视频信号中混入字符信号从而在屏幕特定位置与图像信号同时进行显示的设备。本文介绍了做为计算机接口的字符叠加器原理及电路设计。
关键词 字符叠加器 同步 锁相倍频环 电视中心设备
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Vibration Characteristics of Detached Houses in Japan by Onethird Octave Band Frequency to Environmental Vibration Estimation
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《Journal of Civil Engineering and Architecture》 2011年第11期1019-1026,共8页
In recent years, the complaints against the vibration as environmental pollution tends to increase gradually in Japan. The measurement investigation to demonstrate the actual situation of the environmental vibration w... In recent years, the complaints against the vibration as environmental pollution tends to increase gradually in Japan. The measurement investigation to demonstrate the actual situation of the environmental vibration was carried out for several years. The measurement manual for each vibration source such as operations of factory machine, construction works, road traffics and railways to unify measurement methods was made at the start. From the measurement investigation, the vibration amplification characteristics of the detached house by one-third octave frequency in Japan was analyzed as a purpose to improve estimated precision of the vibration in a detached house. In this paper, the vibration amplification characteristic expressed at onethird octave band frequency was shown, and the characteristics was arranged about a result measured with 27 detached houses in Japan. 展开更多
关键词 Vibration as environmental pollution COMPLAINTS measurement manual Japanese house vibration characteristics.
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