搜索 - 科创

%7B%22c%22%3A%22%E6%96%B9%E6%B3%A2%22%2C%22t%22%3A%22%22%2C%22d%22%3A%22%22%2C%22selectedForums%22%3A%5B%5D%2C%22excludedForums%22%3A%5B%5D%2C%22threadCategories%22%3A%5B%7B%22_id%22%3A21%2C%22name%22%3A%22%E5%8C%85%E5%90%AB%E4%BA%BA%E5%B7%A5%E6%99%BA%E8%83%BD%E4%BA%A7%E7%89%A9%22%2C%22nodeName%22%3A%22%E4%B8%8D%E5%8C%85%E5%90%ABAI%E5%86%85%E5%AE%B9%22%2C%22nodes%22%3A%5B%7B%22_id%22%3A22%2C%22name%22%3A%22%E5%8C%85%E5%90%ABAI%E7%94%9F%E6%88%90%E7%9A%84%E9%87%8E%E7%94%9F%E5%86%85%E5%AE%B9%22%7D%2C%7B%22_id%22%3A24%2C%22name%22%3A%22%E4%BD%9C%E8%80%85%E5%AF%B9AI%E7%94%9F%E6%88%90%E5%86%85%E5%AE%B9%E8%B4%9F%E8%B4%A3%22%7D%2C%7B%22_id%22%3A23%2C%22name%22%3A%22%E4%BD%9C%E8%80%85%E8%B4%9F%E8%B4%A3%E3%80%81AI%E5%8D%8F%E5%8A%A9%22%7D%5D%7D%2C%7B%22_id%22%3A1%2C%22name%22%3A%22%E7%89%B9%E6%AE%8A%E8%AF%9D%E9%A2%98%22%2C%22nodeName%22%3A%22%E4%BB%A5%E4%B8%8A%E9%83%BD%E4%B8%8D%E6%98%AF%22%2C%22nodes%22%3A%5B%7B%22_id%22%3A2%2C%22name%22%3A%22%E6%8F%90%E9%97%AE%2F%E6%B1%82%E5%8A%A9%22%7D%2C%7B%22_id%22%3A13%2C%22name%22%3A%22%E6%97%B6%E4%BA%8B%E6%97%B6%E6%94%BF%22%7D%2C%7B%22_id%22%3A8%2C%22name%22%3A%22%E4%BA%8B%E6%95%85%E6%8A%A5%E5%91%8A%22%7D%5D%7D%2C%7B%22_id%22%3A5%2C%22name%22%3A%22%E5%8A%A8%E6%89%8B%E5%AE%9E%E8%B7%B5%22%2C%22nodeName%22%3A%22%E4%BB%A5%E4%B8%8A%E9%83%BD%E4%B8%8D%E6%98%AF%22%2C%22nodes%22%3A%5B%7B%22_id%22%3A6%2C%22name%22%3A%22%E5%AE%9E%E9%AA%8C%E6%8A%A5%E5%AF%BC%22%7D%2C%7B%22_id%22%3A7%2C%22name%22%3A%22%E7%A4%BE%E4%BC%9A%E5%AE%9E%E8%B7%B5%22%7D%5D%7D%2C%7B%22_id%22%3A9%2C%22name%22%3A%22%E4%B8%A5%E8%82%83%E5%86%85%E5%AE%B9%22%2C%22nodeName%22%3A%22%E4%BB%A5%E4%B8%8A%E9%83%BD%E4%B8%8D%E6%98%AF%22%2C%22nodes%22%3A%5B%7B%22_id%22%3A10%2C%22name%22%3A%22%E9%A2%84%E5%8D%B0%E6%9C%AC%22%7D%2C%7B%22_id%22%3A14%2C%22name%22%3A%22%E4%B8%93%E8%91%97%2F%E8%AE%BA%E8%BF%B0%22%7D%2C%7B%22_id%22%3A12%2C%22name%22%3A%22%E6%95%99%E7%A8%8B%2F%E8%AF%BE%E7%A8%8B%22%7D%2C%7B%22_id%22%3A11%2C%22name%22%3A%22%E4%B8%93%E4%B8%9A%E7%A7%91%E6%99%AE%22%7D%2C%7B%22_id%22%3A15%2C%22name%22%3A%22%E6%A0%87%E5%87%86%2F%E8%A7%84%E8%8C%83%22%7D%5D%7D%5D%2C%22form%22%3A%22%22%7D

50MHz的方波，理论上应该使用450MHz以上的示波器才能将信号中最重要的9次以下谐波准确重新，从而保证波形不失真。

国家无线电监测中心作为无线电管理技术机构，指导下属单位北京东方波泰无线电频谱技术研究所专门建设了业余无线电科普研学基地。

各种调制是可能的发射机频率可以向上和向下杀，如下所示：正弦波，像空袭警报器锯齿波，像从一只鸟啁啾三角波，像美国的警笛方波，像在英国警笛解调范围仅限于传输调制的 1/4 波长。

文件下载

加载中...

你在 {{ downloadTime }} 下载过当前文件。

文件名称：{{ resource.defaultFile.name }}

下载次数：{{ resource.hits }}

上传用户：{{ uploader.username }}

所需积分：{{ costScores }}，{{ holdScores }}下载当前附件免费{{ description }}

下载地址：{{ l.name }}

积分不足，去充值

文件已丢失

当前账号的附件下载数量限制如下：

时段	个数
{{f.startingTime}}点 - {{f.endTime}}点	{{f.fileCount}}

约找到 845 条结果，耗时 0.152 秒

当前账号的附件下载数量限制如下：