Mini Whip active antenna 0.1m vs Delta Loop 33m long, tested on 337 KHz Vranje Airport (Serbia) Non Directional Beacon (NDB) receiving in Macedonia. Receiver is RTL SDR with upconverter.

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):

[ Ссылка ]

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