Excellent VLF receiving system with PC-SoundCard, SDRsharp and Mini-Whip active antenna

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Excellent VLF receiving system with SDRsharp free software, PC-SoundCard and homemade Mini-Whip active antenna.

If your PC-soundcard has 192 KHz samplerate, than you can receive from DC to 96 KHz of RF spectrum.

If your PC-soundcart has 96 KHz, samplerate, than you can receive from DC to 48 KHz of RF spectrum.

If your PC-soundcard has 44 KHz samplerate, than you can receive from DC to 22 KHz of RF spectrum.

The very low frequency (VLF) band of 3 kHz to 30 kHz is used for strategic long range communication from shore to ship, in particular, near-surface submarines. The navies of various countries place a lot of importance to the use of VLF band for broadcasting information to submarines. It is thus a simplex mode of communication. The allocated bandwidth is typically limited to the order of 200 Hz. Because of the limited bandwidth, the message source is only text or data and not voice.
Usually, frequency shift keying (FSK) and minimum shift keying (MSK) have been used as the modulation techniques for VLF communication with data rates of 50-200 bps.

Beside these signals I described in this video, there are much more radio signals, making VLF, ELF and ULF radio spectrum very interesting place for observing an studying.

There are natural radio signals, created by entirely natural phenomena, caused or produced by mother nature, as well as man-made radio signals.

Some of those signals are constantly present, some are very rare.

Signals resulting from natural phenomena are many and varied. Here are some of them:

1. Lightening strikes at various locations around the globe releases a huge amount of electromagnetic energy in wide frequency range from zero right up to visible light frequencies and beyond. It has been estimated that more than thousand thunderstorms are active in the atmosphere at any one time around the globe.

2. Earth surface is under slow but continuous movement of tectonic plates. Their collisions and contractions produced electromagnetic emissions due to giant piezoelectric effect related to huge pressure and crushing of rock crystalline structures.
Many research were made in the past years in effort to make sure about whether large earthquakes are associated with ionospheric changes caused by electromagnetic released by the crushing of rock crystalline structures. If so, than this might be a good starting point to finding mechanism for earthquake prediction...

I am using Mini-Whip homemade active antenna in this video.
Mini Whip is excellent and cheap DIY active antenna.
Especially for lower frequencies! (VLF up to lower HF bands)

Some people who report poor performance of this antenna did not followed the rules of proper installation!
Grounding the outer conductor (shield) of the coaxial cable has to be done properly!
Coaxial cable is part of Mini-Whip antenna and collect a lot of RF noise.
You can treat Mini-Whip antenna as a vertical antenna feeding at the top where the impedance is very high. Outer conductor of the coaxial cable must be grounded at the bottom of antenna, where the coaxial cable touching the ground, and the second grounding have to be done at the point just before coaxial cable entering in the house.
The RF isolating transformer is recommend also.
In that way receiver ground is not physically connected to antenna ground but it is galvanic isolated from outer shield of coaxial cable.
All this measures is not difficult to implement and cost almost no money, but the benefit is clear, noiseless VLF and HF reception!

Mini-Whip antenna must be placed as far as possible from houses, buildings and power lines!

Here is the link of my Youtube video, with schematics of the Mini-Whip and Power supply (power inserter, or Bias-tee for powering the antenna thru the coaxial cable):

https://www.youtube.com/watch?v=DiAO8tCtefc

73,
Mile kokotov, Z33T

Видео Excellent VLF receiving system with PC-SoundCard, SDRsharp and Mini-Whip active antenna канала Mile Kokotov