|Joined:||Sat, Jul 7th 2012, 16:27||Roles:||N/A||Moderates:||N/A|
|Q on dBi, dBd & dB(nothing) vendor data?||Nov 20th 2014, 20:31||2||236||on 21/11/14|
|Drone aka UAV to put up stationary antenna?||Aug 12th 2014, 21:57||2||342||on 5/9/14|
|If I am Tx'ing a VHF GrndWave of how much value is a Beam Antenna?||Jan 6th 2014, 16:54||4||491||on 14/1/14|
|Impedance per current General Manual p.6-6/fig.6-5 ?||Nov 13th 2013, 16:48||1||434||on 13/11/13|
|Why is 72 Ohm Impedance center feed point desireable?||Oct 2nd 2013, 21:10||3||643||on 3/10/13|
|Impedance Matching HF||Aug 1st 2013, 22:18||3||949||on 3/8/13|
|Folded Dipole 40M||Aug 1st 2013, 22:04||3||806||on 17/9/13|
|Q on dBi, dBd & dB(nothing) vendor data?||xof7fox||on 20/11/14|
|When vendors (or even authors of some technical papers) report Antenna Gain with no relative reference to "i"-isotropic (dBi) or "d"-dipole (dBd), and therefore report the gain as simply a certain amount of dB, e.g., 3dB, should one assume that it means the same as dBi? I know that Antenna Gain is always a number that is relative to "something," and yet, as I have said, I see Antenna Gain from time to time reported with no reference to "i" or "d." Many thanks - Fred K4XXK.|
|Drone aka UAV to put up stationary antenna?||xof7fox||on 12/8/14|
|I have done a little time on the internet and found no experimentation, let alone commercial applications, of using drones (aka, Unmanned Aerial Vehicles aka UAVs) to position an antenna and 'sort of' hold it 'in place.' While realizing that this could take more drone heft to lift and hold any antenna that is technologically practical/feasible, I am still brazen enough to risk the embarrassment of posting herein / asking the question. Thanks (I am thinking I just might be hearing laughter in the background? :- ).|
|If I am Tx'ing a VHF GrndWave of how much value is a Beam Antenna?||xof7fox||on 14/1/14|
|Thank you Zack.
Thank you Martin.
- Fred K4XXK.
|If I am Tx'ing a VHF GrndWave of how much value is a Beam Antenna?||xof7fox||on 6/1/14|
|I am struggling to understand the value of a Beam Antenna for 2 Meters IF I am Transmitting an FM Vertically Polarized Groundwave. And, in advance, I thank you for taking the time to read this Post and, further, trying to advise me if you can.
HERE IS MY QUESTION: Does a Beam/Directional help me push the FM Groundwave past the otherwise LOS limitation by some anticipate-able % greater amount?
Meanwhile, with regard to all of the above I do understand that:
1. A Beam will help me Receive (this Q is exclusively about Transmitting).
2. If I am going after a bounce off of Meter/or 'equivalent' Scatter, or making it to a satellite or the space station then the Beam adds to my effective Transmit distance.(this Q is exclusively about Groundwave/LOS, not Skywave).
|Impedance per current General Manual p.6-6/fig.6-5 ?||xof7fox||on 13/11/13|
|While in the current General/Level 2 Licensing Manual (7/1/11-6/30/15) on Page 4-18 "Impedance" is defined as: "...a general term for the opposition to current flow in an AC circuit caused by Resistance, Reactance or any combination of the two."... the Figure 6-5 (GLM0003) on Page 6-6 graphs Impedance over perfect ground per height of a Half-Wave Dipole in Wavelengths, yet it does not say, unless I am missing it, IF the Impedance is that of Resistance OR Reactance. Should the reader assume that the Impedance in Fig. 6-5 is purely Resistance (i.e., that Reactance is zero)?
Many thanks in advance to anyone who can offer to me some guidance on this matter.... Fred K4XXK