Platboom Beach
Here I present my PowerSled 24 kite by Premier Kites hoisting aloft a non-resonant sloper at a taut 60 degrees. Location is the parking lot of Platboom Beach, a popular kite-surfing spot on the Cape of Good Hope in South Africa. Platboom Beach is a very short distance from the world-famous lower and upper lighthouses at Africa's southwetern-most point. Neither this nor our prior Africa trip were DX-peditions. Just normal vacations with Wifey, but not abandoning amateur radio behind meanwhile.
Platboom Beach
Below is shown the lower antenna leg in nearest foreground: 11.4 meters (non-resonant) of 20AWG Ag-plated, stranded Cu with 600V PTFE insulation. That married alongside the kite’s 300lbs braided Dacron line with orange visibility ribbons. Further up-line is my homebrew 9:1 unun with combined 1:1 CMC on identical 1.5-inch OD type 43 cores crammed into a 4-inch OD PVC conduit cap and trailing the major portion of a 25-foot length of RG8X. Above that is another 11.4 length of the same wire, also with visibility ribbons.
Kite Aloft
VIDEO: LINK 18 seconds of the kite and antenna.
To left in the photo below you can see the very taut 300lbs braided Dacron line with orange antenna wire leading up from a GroundGrabba earth anchor. The black leader is 6mm bungee limiting tension on the wire. Nearby to both, laying upon the ground is a green, 10-inch OD yoyo spool showing half of its 500-foot capacity paid out. To right leading up in a catenary is the RG8X feedline. The car is a rental, VW Polo (right-hand drive, as South Africa was formerly British). On the hatch deck is my rig, a Mission RGO One, power 50W. On the fold-up table is my homebrew bank of four, 12.8V 8A/hr LiFePO4 batteries. Out of sight behind the lifted hatch, a 120W Baldr, 4-panel solar array charges the battery most recently used. In the far background is the promontory mountain with upper lighthouse at the very peak.
Hatchback Station
Below is shown the complete setup. The building at left factored importantly in my choice for an all-day solo operation. From this distance the kite line, even with its orange wire and visibility ribbons, shows but poorly. The 4-inch OD PVC conduitd cap containing unun and CMC, closed with a bright yellow cap is quite easily made out, though. That plus also the black RG8X coax trailing therefrom.
The Whole Shebang
To summarize, that’s 22.8 meters of 20AWG (0.8mm OD) wire with a heavy, dual-core unun/CMC at center, the latter trailing RG8X coax. And yet the line remains very taut. Estimating the line between wire terminus and kite as a further 30-some meters, the kite looks to be paid out to 65 meters. Converting to Imperial units, we get 213 feet. Which seems right as the spool, wound with 500 feet of line, appeared unwound by half. For altitude then, the kite flew at around 60 meters (197 feet). Actually somewhat higher, as from this vantage a mild catenary curve is now evident in the line.
My rig is a Mission RGO One from Bulgaria. Max power out is 55W. On receive it draws very low current. So, lots of oomph but still easy on the battery. Out of view to the right is an MFJ-16010 L-Match tuner. Between I have arranged a coax switch and RigExpert AA-30 for no-xmit SWR adjustments. Those two bring SWR down below 2:1 while the rig’s built-in tuner polishes off the remainder.
Tranceiver, etc.
The Morse code paddles at far left are BaMaKey TP-II, which I abuse as a cootie. No microphone at all. Right after opening the box the rig came in, the mic went into a drawer. There it now keeps company with its predicessor from my now-retired IC-745. Which microphone last saw the light of day in 1989.
Stealth mode is the last thing you want in an open parking lot. Winds tend to be variable in that location owing to mountain peaks in several directions save only toward the open sea. Twice it happened that a sudden prolonged lull brought the kite down. That is to say, to the ground, even after shedding the weight of unun and coax with 30m of unladen Dacron to spare.
Said episodes left my line trailing fully across the parking lot and well beyond. Into baboon teritory, as evidenced by their droppings copiously present. Both times I had to hike out beyond the manicured perimiter into the scrub. There I was extremely foot-wary with every step against such potential hazards as puff adders and cape cobras. Many scratches did I acquire upon my bare shins while rescuing my kite and untangling its line from thickets of a plant called fynbos.
As turned out, however, my worst actual hazard to life and limb proved to be a nearly invisible rill. A tiny stream bed all but completely tufted over with grass which ran between the fynbos thickets. Channel width was on par with my forearm's length. But one having cut into the rocky soil to a depth half that again. A veritable micro-Grand Canyon therefor. One into which, had I blunder at walking speed, I might have got off easy just only breaking a leg.
But in all events, the visibilty ribbons alerted the drivers of any cars to my antenna on the ground while I was busy sorting out the above. I can't recommend them strongly enough. There even exists an FAA rule in the USA requiring ribbons every 50 feet, those of a size visible to pilots for a distance of three miles, but only for kites weighing five pounds or more. Which even my largest kite, the PowerSled 36 (left at home on this trip) doesn't come close to. Nor yet the monstrously large PowerSled 81, which I'm to timid to purchase. A giant box kite, perhaps?
The kite line is tethered to a GroundGrabba auger type ground anchor. Zero fear of that being pulled out. The 300lbs braided Dacron line would break first. The antenna conductors end is teathered via a 6mm bungee leader so as to lessen strain on the 20AWG copper wire.
Ground Anchor & Bungee
This is homebrew, my own design, so as to pass muster with the TSA and EU on overseas flights. Maximum allowed power capacity is 100W/hr per battery, but with no limit on how many batteries.
Important Note: Never do I charge the same battery which currently powers the rig. This because the 120W monochrystaline solar panel has 21V capacity in full sun. Said solar panel is power source for a built-in Genasun LiFePO4 charger. A very bad thing has happened to others who weren't aware of the following. An LiFePO4 battery will safely pull down any charging potential to its own volage level only so long as as it is currently charging. The battery's internal monitoring circuits will remove it from the charging path once fully charged. Which can easily happen in strong sun if the rig draws less current on average than the charger potentially supplies. What happens then is that the rig gets slammed with the charger's own full potential of 20VDC plus.
Therefor does my battery bank have eight switches. Four on left to chose which gets charged. Four on the right to choose which is drawn from. Photo taken at start of day with one drawning and none charging.
Battery Bank
Just beneath the folding table you can see my second GroundGrabba earth arnchor being used as an electrical ground. A big red clip with 1/4-inch braided flatline leading up to the rig with its lightning arrestor and also the tuner with its 470 megohms bleed resistor. This against buildup of static from blowing wind.