Historic from 1st prototype to Version 4 final :
On the Tower :
The Author allowed me to do any changes that i wanna do, so design has nearly completely changed...and now is mine own design.
So now "version 4" since Jully 2013, definitiv antenna design, but still a "kind of sloper" , with a lot of changes vs original, dimensions and activ parts, 90% of the secret is in the pipe ;-) But a lot of hours/time/days spended and a bit of € materials.
28 Feb : New coil with less carbon, 65turns + 19.2m sloper untill 1.5m gnd 1.16swr 1840Khz , So was thinking job is nearly done with 3rd version of antenna, but antenna has sometimes too much swr and not stable with wind, weather and nearest house + tower. I ve move it 5meters and 2 SWR. Must found good L + C and the Top hat and if the beams has a too great effect ? diameter of the wire?... must found quickly the solution.
27 Feb : so after few adjust 1.2swr 1820Khz , 68turns + 19.2m sloper untill 1.5m gnd... seems on good ways ... but still some SWR, R 32 , X : 10. Must have a look reactiv and capacity.
24 Feb, Sloper is QRV... on band but 1.9 swr 1850... Z:27Ohms, X ... high ! Too much capacity with slop wire.
1795Khz 1.1 swr Z: 41 but snow is falling , must found a new solution... carbon in matching coil can have an effet...time to try...
20 Feb 2013 16h : So antenna is on tower , I ve begin with 80 turns on the coil @14.5m gnd and + 20m slop until 1.5m gnd :
with 1.5mm2 on coil : 1620Khz / 1.2SWR .
.. So i've redesign the antenna , it was my "1st Prototyp" ... CAT IS NOT INCLUED !!!
So now need to found the good compromise with numbers of turn in the coil and lenght of the sloper wire to change Z and X.
During tests ,40 radials, 10-20m longs are connected to the tower and grounded.
I will try 70 turns and cut 50 cms of the sloper ...
RX is a bit noisy but gain is here, i ve done a french QSO on 1843Khz with ATU of the 756P3 cause Z is 13 Ohms ... so 3.2 SWR.
I ve found a design of wd8dsb in a Mars 1998 QST(ARRL) and the idea was great ; having an antenna to be qrv on Top Band when you have not a lof of place but a 12-15m tower with beams to put a 20m long sloper. But need to improve it for sure.
160m "half sloper" AZF Antenna
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UPDATED 26oct 2015 17h39z - @ f4azf.com
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