Hello rsgb,
Tuesday, September 29, 2015
> Hello Chris,
> The "PCB-antenna" is equivalent to a 1 feet rod and though counter
> intuitive, adding one won't help.
> As with all active whip designs, at VLF / LF / MW and lower HF the
> whip is NOT the antenna.
> How the pa0rdt-Mini-Whip© works, can be found here:
> http://wwwhome.cs.utwente.nl/~ptdeboer/ham/tn/tn07.html
> Though some knowledgeable people don't agree, I have put the theory
> to the test and build a battery powered mini-whip with the battery
> included in the antenna housing. The rf was transported by a
> optical fibre link. The antenna was mounted on a non conducting
> fibre glass pole.
> Nothing was received at all with this set up, until I put a coax
> cable up the mast ending 5 cm below the antenna. There was no
> connection between this cable and the circuit board, whatsoever.
> The shield of the coax cable was connected to a ground stake at the
> bottom of the mast and it provided the necessary ground reference
> for the ohterwise isolated antenna.
> I hope this helps.
> 73,
> Roelof Bakker, pa0rdt
> N.B. Rather than building one for one's own use, which is no problem
> at all, I am sorry to find that some people are making money from a
> copywrighted design. (Readily build antennas are available from the
> designer for those unable or unwilling to build one.)
Thanks for the info "from the horse's mouth", and I sympathize with
your predicament of people selling your design commercially. In this
case I just received a gift from my pal, he has little electrical
knowledge of radio stuff, he must have remembered me saying I would
like to try an active antenna and looked on Ebay. It was my intention
to make one, but he beat me to it, sorry!
It's an intriguing thing and I look forward to trying it out.
--
Best regards,
Chris mailto:[email protected]
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