This aerial, or better electric-field probe, is now in successful use for quite a while (see earlier posts). The design is similar to the one by PA0RDT. To me, this is a very short Hertzian dipole with high Z front-end and a high gain pre-amplifier.
The whip is encased as the two photographs show. Yes, it's plumbing parts that for the enclosure... advantage: waterproof!
The active aerial is use in combination with a Target HF3/W receiver, which supplies 12V for active antennae on the flip of a switch, very handy! The receiver itself is certainly not the best ever made, however, the combination is unbeatable in ease of use for naval weather reports, FAX reception, NAVTEX , Volmet or broadcast reception.