An B3CKS beer can VLF Antenna

  
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So there is a chance to use them in combination with a condenser microphone amplifier for a VLF Receiver. Bingo. The first tests as a Monopole gave good results. I live in a small town located at J041VG with approximately 7500 inhabitants. The height above sea level is between 220-650 m over NN. My QTH is in the middle of town and 330 m over NN.
An B3CKS beer can VLF Antenna - schematic

All the mountains and the buildings are higher than my QTH. To top it all I have many signals interfering with VLF reception such as power line hum, broad-band RF and possibly modem or cable TV interference. I hear many signals from the VLF band up to 108MHz. Certainly not good for VLF listening. I`ve tried numerous types of Antennas but so far not much satisfaction. The Magnetic type antennas (ferrite and loop) give good reception of sferics, but, unfortunately too much hum and RF. All attempts to blank out this interference reduce the sound quality of the sferics. So I tried different electric antennas. With some of them I was able to listen to the VLF band without too much hum and interference at my QTH. Unfortunately I do not have the room to put up large antennas. The receiving of sferics is shielded by building around me and the broadband signals produce an incredibly loud background noise. The bulk of the interference is between 3. 5KHz to 6. 5KHz and 8KHz to 11KHz. No other options. I must go out to open country. The first test of the antenna gave a very good result. . until sundown! Suddenly I heard many Radio Stations from different Countries and the signals faded in and out in varying cycles. So I was frustrated by this and went to bed. But someone :-) told me: "You have to change the capacitors in the circuit. " The circuit is modified by changing C4 & C7 to 1. 5nF to block the RF signals and adding 15nF to R10...



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