Tuesday, April 25, 2017

10 Ultra Stealth Antenna Designs for HOAs. Post #1112.

10 Ultra Stealth Antenna Designs for HOAs
(http://forums.qrz.com/index.php?threads/10-ultra-stealth-antenna-designs-for-hoas.260566/).
Author:  KC8VWM.
Accessed on 26 April 2017, 05:35 hrs, UTC.
Please click link to read the full article.

Comment:

Operating from a deed-restricted property can be challenging.  Just because the "housing police" says "no antennas" doesn't mean you can't get on the air.  You have to be clever and "stealthy" to erect an antenna where restrictive rules are the order of the day.

In this article by KC8VWM, we learn how common, everyday objects such as old satellite dishes, bicycles, and even a badminton net can be used as makeshift antennas without your neighbors even knowing about your real intentions.

Here are 10 ideas for making an "ultra stealth antenna" in deed-restricted housing:

Use a Weather Instrument project as an antenna.
Solar powered lights can be used for informal vertical antennas, especially for 20 through 10 meters.
Old satellite dishes can be remade into VHF/UHF antennas.
The detachable speakers from an old AM/FM portable radio can be used to support a small dipole antenna.
Build a Purple Martin Birdhouse on a tall pole.
Make a tire swing vertical.
Make a badminton net antenna.
Use a bicycle to support a vertical helix antenna.
Use a long crappie fishing pole leaning against your house as a vertical antenna.
Use a patio umbrella loop.

This list should give you some ideas for operating under restrictive circumstances.

For the latest Amateur Radio news and information, please visit these web sites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

Other sites of interest:

http://hawaiisciencedigest.com (science and technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, politics, terrorism, and cybersecurity).

Be sure to check the blog sidebars for more antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM)

Monday, April 24, 2017

J Pole Antenna Design Calculator by K4ABT

J Pole Antenna Calculator by K4ABT
(http://www.hamuniverse.com/jpole.html).
Author:  G.E. "Buck" Rogers, Sr. (K4ABT).
Accessed on 25 April 2017, 04:55 hrs, UTC.
Please click link to read the full article.

Comment:

Thanks to G.E. "Buck" Rogers, Sr (K4ABT) for this ultra simple, easy to understand J Pole Antenna Calculator for HF, VHF, and UHF amateur radio bands.  Just enter the operating frequency and calculate the dimensions of your J Pole Antenna.  Using this type of antenna can be a bit tricky, so G.E. recommends the following additional step:

"On most of the J Pole designs out there, a choke should be used as close to the feedpoint of the antenna as possible to help prevent rf on the feedline and creating difficulty with SWR readings. For 2 meters, the coil is 4 turns of coax at 5 inches in diameter. You should get good results with the choke within 3 or 4 inches of the feedpoint on 2 meters.
Hint:
Use the last part of your feedline as the choke before attaching to the feedpoint!"

I've made a few J Pole antennas over the past few years, and they work great on the VHF and UHF bands.  J Pole antennas should give you about 3 dB gain over a monopole antenna.  One of these days, I'll make a J Pole antenna for 20 meters. That should be an interesting project.

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

Other sites of interest:

http://hawaiisciencedigest.com (science and technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, politics, terrorism, and cybersecurity).

Be sure to check out the blog sidebars for more antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM)


Sunday, April 23, 2017

Adding 80 metres to a 40 metre dipole. Post #1110.


If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=4kXRz6fPFKY.

If you live on a small urban or rural lot, erecting a full-size 80 meter horizontal dipole antenna can be quite a task.  In this video from Peter Parker (VK3YE), we learn how to convert a 40 meter horizontal dipole antenna into a serviceable dipole for the 80 meter band.  The secret is to add loading coils to both ends of the dipole antenna.  Peter supplies the necessary coil winding data, materials list, and tuning procedures to get your old 40 meter dipole working on the 80 meter band.  Although this modification won't be as efficient as or capable of the same bandwidth of an 80 meter dipole, this antenna will get you on the air from a small size lot.  You may even be able to operate this antenna on the 3rd harmonic of 15 meters, where the 40 meter portion of the dipole will serve as a 3/2 wave length antenna on 15 meters.

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

Other sites of interest:

http://hawaiisciencedigest.com (science and technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, politics, terrorism, and cybersecurity).

Be sure to check out the blog sidebars for more antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM)

Saturday, April 22, 2017

Antenna Loading with Coils. Post #1109.


If you can't view this video, please insert this title URL into your browser search box: https://wwww.youtube.com/watch?v=XjtE_SZjQ-g.

In this video from Stan Gibilisco (W1GV), we learn the a classic way to shorten a dipole antenna without sacrificing performance and ease of operation.  If the coils are built correctly, you will lose only a small percentage of the signal normally found on a full horizontal  half wave dipole antenna.  Stan does a good job of explaining the theory, design, and operation of this easily made HF antenna.  This antenna is a good compromise for radio amateurs living on a small city or rural lot.

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

Other sites of interest:

http://hawaiisciencedigest.com (science and technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, politics, terrorism, and cybersecurity).

Be sure to check out the blog sidebars for more antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM)

Friday, April 21, 2017

Homemade 70cm Yagi Beam Antennas. Post #1108.


If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=1WI6Cy4ovig.

Here are two excellent examples of 70 cm Yagi beam antennas made from commonly available materials.  The first antenna is a 7-element beam with a wooden support structure, while the more polished 10-element beam uses aluminum to support the antenna elements.  Both antennas, along with a sturdy rotator atop a small mast, will give you excellent performance between 430-440 MHz (70 cm).  You can cut the antenna elements to conform to the 70 cm allocations in your area.  Video supplied by M0UKD).

For the latest Amateur Radio news and information, please visit these websites:

http://www.HawaiiARRL.info.
https://oahuarrlnews.wordpress.com.
https://bigislandarrlnews.wordpress.com.
http://www.kh6jrm.info (breaking news for radio amateurs).

Other sites of interest:

http://hawaiisciencedigest.com (science and technology news for radio amateurs).
https://hawaiiintelligencedigest.com (trends in geopolitical intelligence, strategic forecasting, terrorism, and cybersecurity).

Be sure to check out the blog sidebars for more antenna and propagation articles.

Opinions expressed in this blog are mine unless otherwise stated.

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM)