Mast Mountable J-Pole Antenna
The J-Pole antenna’s long and storied design history is due for one more chapter to mitigate the longstanding mast current and reliability issues.
Antennas
Simulations and testing are shown in these articles about ham radio, and a few other, antennas.
Have your J-Pole and ground it too
Tame the predictable mast currents found in any j-pole antenna grounding conductive mast using a simple stub. Shown is empirical evidence why this is a problem and a very simple solution all future grounded j-pole antennas should incorporate.
New Choke Configuration for AHVD
Shown is a better configuration to fasten a choke to the Asymmetrical Hatted Vertical Dipole antenna.
Diamond X50 Antenna Measurements
I measured the SWR and Return Loss of a loaner Diamond X50 antenna.
3D Model for AHVD Antenna
Presented is a 3D E-Drawings rendering of the Asymmetrical Hatted Vertical Dipole antenna.
The Coaxial Dipole
G4CQM provides details on a Yagi-Uda coaxial dipole driver approach for designers lusting after a 50 ohm self-balancing feed.
Repeaters, Antennas & Trigonometry
You need an antenna with energy at high take off angles to hit the hill top repeaters… right? Well, not likely. Let’s review the details and do the math to understand what’s needed for VHF terrestrial radio communication.
Hoverman TV Antenna Measurements
Doyt Hoverman’s 1960s TV antenna design placed over a simple reflector screen provides impressive performance for today’s UHF and VHF-HI television bands.
AHVD Winter Wonderland
The Asymmetrical Hatted Vertical Dipole (AHVD) worked quite well for some 10m contacts even with a load of ice on the elements.
HF AHVD on 6m – Practical?
Will the KX4O version of the 20-10m Asymmetrical Hatted Vertical Dipole work on 6m? Yes, sort of.
This Balun Chokes
Jim (K9YC) Brown’s toroid winding recipes provide a superb RF choke balun for 30-10m using RG316 and a #43 toroid.
Hatteras Ham Shack
I took the asymmetrical hatted vertical dipole to Hatteras beach to activate NA-067. I wasn’t very successful, but made a couple QSOs. Despite mixed results, the setting was spectacular. The vertical dipole worked.
Vertical Dipole at Lighthouse
The asymmetrical hatted vertical dipole (AHVD) provides a quick setup HF antenna at Hatteras lighthouse.
Build this Vertical Portable HF Antenna
The Asymmetrical Hatted Vertical Dipole (AHVD) prototype is an easy to build, portable alternative to other freestanding vertical HF antennas such as the Buddipole.
Asy Hat Vertical Dipole
We re-introduce the theory and origins of Cebik’s (W4RNL) Asymmetrical Hatted Vertical Dipole (AHVD) antenna with the hope to facilitate a vertical polarization portable 20-10m aerial for portable operations.
40m Mastless NVIS Antenna
Yet another 40m Cloud Burner design featuring a folded dipole driven element plus one reflector wire to facilitate 40m NVIS contacts without need of a tall mast. The design uses electric fence posts for support and needs no balun.
40m Loop Ground Wire Test
In the name of science I cut the wire laying on the ground underneath my 40m fullwave horizontal loop to see what would happen.
Wideband 80m Dipole
A 1/4 wavelength of 75 ohm coax inline with a full wavelength of 50 ohm coax is all one needs to make a simple 80m dipole become a wideband dipole antenna.
Superbowl HDTV Antenna
Build the venerable Hoverman TV antenna and watch digital broadcast high definition HDTV television this weekend. This version of a HDTV antenna uses amateur radio antenna building techniques to make a lightweight structure.
SWR of Several Mobile Antennas
I had occasion to test four popular amateur radio mobile antennas. Here are the results of SWR and Return Loss of a Diamond SG7900ANMO, Larsen NMO 2/70, Cushcraft CS-270M and Laird QW144.
Assemble the 6m LFA Yagi
This final installment about the 6m LFA Yagi Antenna shows the technique to hold copper pipes to the boom using home center PVC plumbing materials.
Cutting Copper for 6m LFA Yagi
Here is a step by step photo album showing how I prepared home center copper pipe for use in a three element Loop-Fed-Array Yagi-Uda antenna (aka LFA Yagi Antenna).
Copper 6m Coplanar LFA Yagi-Uda
The Coplanar Loop Fed Array (LFA) Yagi-Uda design from G0KSC provides an excellent design foundation for an all copper version of a 3 element 6m balunless beam with superior front to back performance. Shown are comparisons between model simulations and prototype measurements.
Coplanar Loop Fed Array LFA Yagi-Uda Antenna
The clever application of the folded dipole loop, computer science iteration techniques and NEC simulation to Yagi-Uda design results in a panoply of practical planar Loop Fed Array, LFA Yagi antenna recipes.