7VM | |
7 mhz -vertical monopole - high efficiency half wave vertical radiator - fisical lenght= 8 mts ,very low radiation angle, multi-loading to keep losses low,good decoupling system , no radials needed , just a short counterpoise | banda 40m, monopolo verticale mezz'onda,ma fisicamente lungo 8m,basso angolo di radiazione alta efficienza,non ha bisogno di radiali,solo un contrappeso, efficienza esaltata dal sistema a caricamento misto adottato |
tips and notes = coil= 14 turns,bifilar
winding (2x1.5mm)-spaced-coil lenght: 85mm
; Coil diam.= 80 mm; L=12uH; Link:2 turns
on the cool-side (ground).Capacitive hat:see
picture Antenna winding: copper-tape 10mm wide;0,1mm thick,overall lenght: 41,04 meters.C=45pF made by RG58(almost 0.9pF x cm ) important note:insulate the end of coax capacitor and cut the brade shorter than inner wire.This procedure will void electric arc on the coax tip .Insulate by rubber-tape counterpoise: 2,8 m,aluminum rod (antenna mast) insulated _ Antenna : 8 m , fiberglass fishing pole. SWR= 1:1 , bandwidth 100khz with swr = 1:1,5 | |
For best results this antenna takes advantage of distributed inductance,capacitance and capacit_hat | |
---|---|
antennas |