J-Pole antenna is an end-fed omnidirectional antenna that should be fed with 50-ohm impedance balanced line. When fed with coax (whether it is an RG-58 or RG-8) cable, it should be connected with air-choked balun.
There are several variation of J-Pole antenna, including the Slim Jim and also the ladder-line J-pole suitable to be used with hand held transceiver.
Here is the plan for a typical J-Pole antenna (measuremant in inches):
Copper tubing is usually used as the construction material for J-Pole antenna.
A mounted J-Pole antenna:
Alternatively, you can buy ready-made J-Pole antenna for hamradio transmission from KB9VBR J-Pole Antennas.
Magnetic loop is an ideal antenna for Ham radio HF operation particularly because it is relatively small and portable when compared to other forms of HF antenna.
Here are some videos demonstrating the use of Magnetic Loop antenna
W2BRI has a page on how to build Magnetic Loop for HF operation.
Here is a plan for homebrewing a 2 Meter Square Dipole plan. The advantage of this antenna is that it is unidirectional, and it takes less space than the regular 2 meter dipole. The calculation included on the diagram below is for building the antenna using copper tubing, you should use MMANA-GAL or other antenna simulation software to come up with new dimension for other materials (aluminium, wire, etc).
Click on the diagram to enlarge it. Hopefully this will help you in brewing new antennas! Original plan taken from KOFF website
My friend, 9W2AZV gave me the drawing for this 2 meter antenna, I haven’t tried building it yet. The antenna seems to share common design with a collinear antenna. I ran this schematic in MMANA-GAL and found out the antenna has a very nice flat radiation pattern which maximize the transmission reach.
Here’s the the antenna design:
Tak-Tenna is a type of compact antenna which is suitable for those who has space constraints on erecting their HF antenna. It is small enough that a 40 meter Tak-Tenna is just about the size of a 4-element Yagi 2 meter antenna. Here’s photographs of 40-meter Tak-Tenna in action. Compare that to the typical 40-meter dipole or Inverted-V configuration ! Thus it has the advantage of space-saving and unobtrusive setup when compared to other design of HF-antenna.
Tak-Tenna is available in 3 models – 40, 20, and 10 meters, with the 40 meter model can be use on 40, 30, 20, 15, and 10 meters with a tuner.
Refer to this article: “The TAK-Tenna™ Review – A Limited Space HF Antenna Review” for further review on Tak-Tenna performance and advantages.
Tak-Tenna can be ordered from the official Tak-Tenna website
Here’s the simplest antenna that you can build to transmit with your HT or mobile rig when you have nothing else to rely to. The configuration gives you a 3.5dBi gain and it is simple to construct when you’re at outdoor.
I built this antenna, specially for hitting repeaters during lightning storm, as my usual high mounted antenna might attract lightning.
This antenna can be built using any conductive wire. Though, for my configuration, I use thick copper wires with the length A = 0.525m and B=0.4815m. The A-B angle is about 100-110 degree. It gives SWR 1.0 between 145.5MHz – 145.8MHz and SWR 1.3 at 148.0MHz, the edge of 2 meter amateur radio band.
Here’s a 12 Element UHF Yagi antenna that I designed for my friend, 9w2azv. He’s going to use that antenna for his client, that needs to hit a repeater 10 kilometers away from their location.
Here’s are the measurement for the antenna :
Polar Plot for the Antenna (E-Plane)
Polar Plot for the Antenna (H-Plane) at 2 Wavelength height
Here is the YagiMAX file : 10 Element Yagi 457MHz
Here’s a diagram for a simple 10m loop antenna. Although 10 meter band is not very good at this time of the year, the operating condition is predicted to be improving in the next couple of years.
Simple Antenna for 10 meter operation
A/B Value for 28.2 MHz
A = 73″
B = 146″
A/B Value for 28.5 MHz
A = 72″
B = 145 3/4″
A/B Value for 27.5555 MHz (freebander)
A = 73 1/2″
B = 150 3/4″
Data from MMANA-GAL software
The antenna can be build from Copper wire or aluminum tube.
Here’s the MMANA-GAL file for reference : 10meterloop_simple.maa
I took some time off to build my first HF antenna using the plan I’ve obtained few months ago. I chose moxon as my first 10 meter HF antenna as it is small and compact and it is directional, allowing me to focus it into a single direction for a pretty quiet QSO, without much interference.
The material I used in building this moxon are :
- Green ground (12 Gauge ?) wire, it has 7 copper wire inside it.
- PVC pipe (3/4″ diameter) as necessary to hold the wire in place, you can use other materials too, as long as it formed the basic dimension of moxon antenna
Antenna Plan and Results
I use the plan described in this post; 10 Meter Band Compact Directonal Antenna and started building it immediately. The result of the antenna can be seen here :
Although I build it only as a temporary antenna (thus its flimsy), it performed rather well when compared to other types of popular 10 meter band antenna in my place (Delta Loop, Inverted-V) as the antenna is directional and it does not requires the use of transformer balun.
I’ve managed to make contact with 12 stations in 6 days since it has been erected.
Some tips working on 10 meter band
- Use a good low loss cable such as RG-8 or Belden 9913
- Make sure you know where you point your antenna, the direction of your antenna is crucial if you ever to make contact with distant station.
- The propagation is pretty good during daytime between 3pm – 8pm by my observation, use that time window wisely.
Use directional antenna like Moxon or Yagi as they allow you to focus your transmission to a certain direction and eliminate excessive interference on the band.
- Be patient
That’s it and good luck!
I wouldn’t recommend PVC pipes if you are planning to erect a permanent antenna as they are flimsy. Use aluminium pipes or copper tubes as they are more durable and offers best performance.
I’ve been searching for information regarding the radiation angle and the gain of slim jim antenna, but found none of it. So I decided to build the model of the antenna inside the ever useful MMANA-GAL software to get the information I needed myself.
From what I can surmise, the slim jim has a slightly lower radiation angle than vertical dipole antenna and is easier to mount, thus it is suitable to use for point-to-point communication VHF-UHF operation. It has a gain of about 2.8dBi-3.2dBi in free space and 4.8-5.8dBi when mounted at about 30feet from the ground. Here’s the result of MMANA-GAL :
Slim Jim mounted 30 feet above ground
Slim Jim in free space