|The PA0RDT Miniwhip is good at ruffling feathers amongst the antenna pundits, and it deserves a little more context beyond a one liner "great" or "snake oil".|
I purchased my PA0RDT Miniwhip(s) direct from the designer Roeloff after reading about it on the merseyradar website. It is extremely well put together and the cost is insignificantly different from all the myriad clones. Also I can confirm from direct experience that Roeloff provides a great back up too.
I have it installed just above the top of a 1.5 metre glass fibre mast, about one metre above the ridge line at the rear of my house, so it must be about 8-9 metres AGL. I installed triple cascaded FT140 chokes of 31, 43 and 77 mixes directly at the antenna's feedpoint, and I sometimes use it with a duplicate triple choke array at the shack end too. My logic there is that with the Miniwhip being so broadbanded, I can throttle all the unwanted SW signals bring picked up on the braid if the coaxial is indeed the main source of the signals as many claim. More significantly I have never "grounded" the coaxial feed to the Miniwhip under any scenario- any "ground" it benefits from is by virtue of the coaxial braided screen back to the shack. Basically, I have eschewed the suggested installation instructions and it shouldn't really work. I use it primarily to listen to SAQ on 17.2 kHz.
If I kill the DC supply to the antenna, all the signal including noise disappears. Similarly if I switch off the Datong LF converter everything disappears. I can say that for SAQ on 17.2 kHz it works very well for me. I have used one at a remote and pleasingly very low noise level location in a valley surrounded by a 600 metre skyline on a couple of occasions, mounted atop a 5 metre roach pole all off grid (again- no "ground") and I received an extremely strong signal from SAQ both times.
According to the way I have been using it (no "ground" and a heavily choked feeder) and taking into account the various well qualified internet naysayers, it should not work, but it does. Would I buy it again? I already have done- that's how I take it to the remote location without having to climb onto my roof to take the original one down.
From my unrepresentative sample of two, I have no hesitation in recommending the Miniwhip provided you go into it with both eyes open and manage your expectations accordingly, but as usual your circumstances will inevitably be different from my own and your mileage may well indeed vary.