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if we move the feedpoint from the center of a full wave dipole 1/4 wl to either side of center it feeds just the same but the radiation pattern will be noticeably different when compared to a center fed 1/2 dipole. this works as long as each half of the dipole is any odd number of 1/4 wl. in...

"That is for one station to horizon" The antennas (plural) at both ends are assumed to be at or near ground level. this is the case in: https://vu2nsb.com/radio-propagation/ground-wave-propagation/surface-wave-propagation/ antennas at ground level and 100W. also the case in...

VU2NSB in India S9 @ 7 kM with 100W (4.35 miles) 30 dB. additional path loss S4 @ 35 kM with 100W (21.75 miles) 18 dB. additional path loss S1 @ 80 kM with 100W (49.70 miles) @ this point if we increase radiated power to 1 kW. to overcome an additional 10 dB. of path loss that puts the...

so no one in this forum has ever worked any of their local stations on 11 meters beyond distances of 12 - 15 miles via ground wave propagation. IW5EDI in Italy http://www.iw5edi.com/ham-radio/3233/quarter-wave-vertical-antennas

interesting. what are both of you using for antennas?

anyone?

it's the international telecommunications union telling anyone who cares to read that ground wave communications are possible @ 30 mhz. out to 150 kM. over medium dry ground and out to 360 kM over sea water with average salinity, not me. they made the decision to run the tests with both the...

a ground wave radio signal is made up from a number of constituents. if the antennas are in the line of sight then there will be a direct wave as well as a reflected signal. as the names suggest the direct signal is one that travels directly between the two antennas and is not affected by the...

"Ten meter ground wave (direct) propagation is much more predictable than "sky wave". Local contacts up to 40 or 50 miles or more can be expected 24 hours a day and is very useful for local communication." ~ Dan Butler, N4UJW ~

"I tried 3 different antennas" what antennas?

The BIG problem is that probably 99.999% of CBers and a significant % of amateurs have been told in various publications over the years that ground or surface wave propagation @ both 10 and 11 meters is impossible at distances beyond 6 - 7 statute miles or 10 kM.. this is clearly not the case as...

"Groundwave propagation on 11 meters???? REALLY?" GROUND-WAVE PROPAGATION CURVES FOR FREQUENCIES BETWEEN 10 kHz AND 30 MHz. over 11 different types of signal-path soil conditions. the propagation curves in this recommendation are calculated based on the assumption that both the transmitting...

when looking at a sine wave signal we understand that one cycle is equal to the distance from either one crest or trough to the next crest or trough. here's the question. if @ a frequency of 27 mhz this cycle repeats itself 27,000,000 times every second, what is the amount of time required for a...

dipole antenna animation: + = charge, - = discharge, charge to charge or discharge to discharge = one cycle. at a frequency of 27 mhz. one complete cycle occurs every 3.703 nS. (nanoseconds) this is only 1/2 the picture since the magnetic (current) h-field component has been omitted.

try this, the blue area is the (electric field) e-plane and the red area is the (magnetic field) h-plane. an antenna is a transducer, during transmitter operation it converts current and voltage into transverse electromagnetic energy while in receive mode it intercepts varying amounts of...

"I thought they had a fixed phase relationship." if that were really the case then there would be no transverse electromagnetic "radiation." radio frequency signals are (alternating current) ac signals. current and voltage had better both be "changing."

in the case of either the center fed dipole or the common 1/4 ground plane worked against a ground system when the voltage and current traverse the distance from the feedpoint to the ends of the elements they are now (@ the ends) out of phase with the current and voltage @ the feedpoint. when...

your "education" provided by commercial antenna manufacturers and "hobbyists" is in error, the opening statement is irrefutably correct. maximum feedpoint current (low impedance) only occurs when the 1/2 antenna is center fed, when end fed feedpoint voltage is maximum. (high impedance) from...

"Perfect resonance and flat SWR will provide greatest Effective Radiated Power". not so. an antenna exhibiting a radiation resistance of 14 ohms and total loss resistance of 36 ohms will perform poorly when compared to another antenna exibiting a radiation resistance of 36 ohms and total loss...

Blaster posted: "and there was me thinking 1/2 waves were resonant." an end fed 1/2 λ is not self-resonant however a center fed 1/2 λ is self-resonant. a wire 90, 270, 450 (any odd number of 1/4 wl, in length) degrees long @ any given frequency is i.e., SELF RESONANT, not "resonant." theres...