Comment on Mast ideas and recommendations
667@lemmy.radio 3 weeks agoThe window line j-pole is a monoband vertical, a half wave radiating element and a quarter wave impedance matching section. On 20m the overall length of this thing is 14.4m.
On my current mast, the radiating element comes down to about 1m off the ground and then I have the matching section strung perpendicularly across the fence to keep it off the ground.
AE5NE@lemmy.radio 3 weeks ago
Have you tried a 1/4 wave vertical with 4 radials sloping towards the ground? (all wire)? or even a vertical dipole fed halfway up? J-poles show significant coupling to their feedline and mounting arrangements and, as you discovered, are taller than they need to be for their gain.
667@lemmy.radio 3 weeks ago
I haven’t tried any radials, and tbh I’m not certain to where I would attach them given the j-pole design has a matching network in-built. I’ve got a 1:1 balun at the feedpoint and an inline choke at the radio. My 10m antenna of identical design is great, and this one is great too (I see ~1:1 at 14.250), it’s just much higher in the band than I had planned and I strongly suspect it’s simply ground reflection since the radiating element is way lower than the halfwave it ought to be.