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/diy/ - Do It Yourself

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>> No.1333773 [View]
File: 865 KB, 1440x900, noise.png [View same] [iqdb] [saucenao] [google]
1333773

>>1333756
Often it's much worse than that, here is overnight recording. 160m is unusable completely, 80m is full of noise and only local hams can make it (like few kilometers away), so it's unusable as well, only 40m is somewhat better as sometimes you can find a noise-free spot.

I also have FM radio/TV tower within like 2 miles away, well I have extremely strong FM & TV signals here, so strong that shit makes measuring RF stuff tough due to interference and it also rules out many if not all active antennas due to intermodulation distortion of preamps (I build two active loop antennas, all performed shitty, not only they pick up local noise but also TV & FM transmitters generate shit load of interference everywhere).

>>1333750
>Perhaps you mean a 9:1; unless you are transmitting with it I wouldn't worry too much about matching it.
It's 1:9, 1 side goes to coax, 9 side goes to wire. I also tried 1:4 and 1:16, 1:9 seems to be the best overall.
http://www.dl1glh.de/beverage-unun/beverage-unun.html

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