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Showing posts from April, 2015

Simple Ham Radio Antennas--Building Ladder Line by N4LQ. Post #424.

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Nice, simple tutorial from Steve Ellington (N4LQ) on how to build and install spreader insulators for ladder line. Choose your own spacing. Wire ties should be at lease twice the length of the spacer. If UV damage is a concern, spray the assembly with Krylon UV paint. Although the construction of homemade ladder line is a bit tedious, the reward is having a feed line that can transform a single band dipole into a multiband antenna. With the ladder line connected to a 4:1 balun and then attached to your rig with a short length of RG-8 coaxial cable, you will have an antenna that can cover several HF bands. At my QTH, I have a 40 meter inverted V antenna that covers 7.000 MHz through 29.990 MHz by using homemade ladder line, a 4:1 W9INN balun, and my trusty Drake MN-4 antenna transmatch. You can also buy 450 ohm ladder line through the various Amateur Radio store outlets, but it's more fun "to roll your own." My ladder line is made from #12 AWG house wire, old pla…

Nepal earthquake report #6 | Southgate Amateur Radio News. Post #423.

Nepal earthquake report #6 | Southgate Amateur Radio News: This page is brought to
you in association with The Southgate Amateur Radio Club and the Communications Gateway, Limited.
 Page last updated on: Thursday, April 30, 2015 . Nepal earthquake report #6.

The Nepal Amateur Radio Society continues to provide emergency communications during the ongoing rescue effort, despite power cuts and damaged communication infrastructure.

Satish 9N1AA along with daughter Tej 9N1DX are using solar power in coordination with the Nepal police in Kathmandu. Also sharing the emcomm work using handhelds and 20m, was Suresh 9N1HA, Pravin 9N1KK and Akarsha 9N1ZZ.

Missing persons inquiries are being handled, and these need to be checked against lists held by the Red Cross at these links.
http://google.org/personfinder/2015-nepal-earthquake/

http://familylinks.icrc.org/nepal-earthquake/en/pages/home.aspx

There will be a more complete casualty list available as the Red Cross increases relief work.

Rescue t…

Nepal Grants Operating Permission, Call Signs to Visiting Hams, as Earthquake Recovery Continues. Post #422.

Nepal Grants Operating Permission, Call Signs to Visiting Hams, as Earthquake Recovery Continues:

TAGS: Amateur Radio HF, amateur radio society, cell phones, ham radio, ham radio operation, hams, Jayu Bhide, Nepal, recovery effort, rescue teams, telecommunication infrastructure
04/29/2015.
In the wake of the devastating April 25 earthquake, hams in Nepal, already in limited supply, have been turning out to help in the ongoing recovery. The Nepalese government also is reported to be cutting some of the red tape that has prevented hams from outside the country from operating within Nepal. Several hams from India are among those who have arrived in Nepal to help facilitate communication. Word earlier this week via Amateur Radio Society of India President Gopal Madhavan, VU2GMN, was that visiting hams would not be permitted to operate in Nepal, unless they were part of a government team.On the other hand, getting needed Amateur Radio equipment into Nepal has been problematic.

“ARRL is wor…

Simple Ham Radio Antennas--Build a Portable 10 Meter Yagi Antenna. Post #421.

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A nicely built 2-element 10 meter yagi antenna for field day or for portable use. Dave Tadlock (KG0ZZ) does his usually good job in explaning the theory behind the antenna, the kind of materials needed for construction, and how to use the antenna to your best advantage. Dave says it's also possible to build the yagi out of pvc pipe and wire, "but the pvc pipe will need a 1" x 8' wood dowel or 'closet pole' for a stiffener." Good luck in this upcoming Field Day during the last full weekend of June. I'll have more Field Day antenna suggestions in forthcoming posts. There's nothing quite as satisfying as building your own antenna and seeing it "do its stuff." For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. You can get more Amateur Radio news by visiting my ne…

Simple Ham Radio Antennas--The MFJ-1786 Magnetic Loop Antenna is fantastic! Post #420.

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Well-produced video from "The Radio Hobbyist" showing the unpacking, set up, and use of the MFJ-1786 Magnetic Loop Antenna. The set up seems straight forward and fairly easy. This particular loop was installed about 5-ft/1.52 meters above ground level and performed about as well as the operator's dipole. This antenna would make an ideal portable or emergency antenna. Those living in deed-restricted areas (HOAs and CC&Rs) could find this antenna useful in getting on the air without being seen. The MFJ-1786 Magnetic Loop Antenna is a bit expensive (around $450), so you may want to "roll your own" following a design such as the "Alex Loop Walk Ham Antenna." My use of loop antennas has been on the larger size--my current HF antenna is an 80-meter delta loop fed with 450 ohm ladder line into a 4:1 balun and then into my Drake MN-4 antenna transmatch. I get 80-10 meter coverage and a very quite receive antenna. For the latest Amateur Radio ne…

Simple Ham Radio Antennas--Standing Waves Part II: Explanation. Post #419.

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Here's part II of James Dann's tutorial on standing waves and harmonics. Dann explains the derivation of the harmonic frquencies on a string attached at both ends. He shows by experiment how the appropriate formulas are created. A well-presented and thoroughly understandable physics lesson. As mentioned earlier, this video could be used in a high school physics class or in an Amateur Radio Technician Class program. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated frequently. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. You can also visit my news site at http://kh6jrm.net. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--Standing Waves Part I: Demonstration. Post #418.

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A basic knowledge of standing waves and their harmonics is key to understanding antenna theory. Instructor James Dann presents the basic facts of standing waves in this outstanding, easily digestible video using the simplest of tools. This video could be used in a high school physics class or in a presentation to people preparing for the Amateur Radio Technician Class License exam. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. You can get more Amateur Radio news from my news site: http://kh6jrm.net. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--Multi-Band HF Vertical Antenna. Post #417.

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If you have difficulty viewing this video, please enter this URL into your browser--https://youtu.be/pi8ysNBDDBg. Here's an example of a simple, no-frills vertical antenna that will provide hours of fun at your ham station. This antenna design from N0ECK and the folks at resistance hams can be assembled from materials you may already have in your shack or garage. You can also find these materials at your local hardware store or building supply outlet. The steel shed serves as a ground plane. I've built a few mono-band antennas using the same principal. Currently, I have a 20 meter vertical attached to my garage with the ground wire attached to the metal roof using a stainless steel bolt and screw assembly. The antenna works quite well for a vertical. For the latest Amateur Radio news and events, please check out the blog sidebar. These news feeds are updated daily. You can find more Amateur Radio news on my two news sites--http://kh6jrm.net and http://www.myalltop.com/…

Simple Ham Radio Antennas--The Double Bazooka Antenna - A Review. Post #416.

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A comprehensive review by Rob Wagner (VK3BVW) of the 40 meter Double Bazooka Antenna made by IAC Antennas (http://www.iacantennas.com). Rob's video explains the theory behind the bazooka antenna and how it can be erected safely. The 40 meter version of the antenna is 51 meters long (167.28 feet) and is made from RG-58 coaxial cable and 300 ohm twin lead. The antenna is fairly immune to noise and offers some gain over a dipole antenna. There are two caveats concerning this antenna: The antenna is longer than a half-wavelength 40 meter dipole and is a bit heavier than its half-wave cousin. You will need two strong end supports for the antenna, since it tends to sag in the middle. You may also need another person to help you erect the antenna. My experience with the double bazooka antenna is limited to a 10 meter version I made as a general class operator back in the late 1970s. That antenna was homebrewed and performed very well. If you wish to build this type of antenna,…

Simple Ham Radio Antennas--How to build a Delta Loop Antenna. Post #415,

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A clean, simple tutorial by Hiram Varquez on how to build a delta loop antenna and a Q-Match for it. According to Varquez, "The Q-Match will make the antenna resonant at 50 ohms at the feedpoint. This eliminates the need for an expensive balun." The delta loop antenna is bidirectional and exhibits some gain over a dipole. The loop is compact, easy to build, and inexpensive. Although Hiram's delta loop is designed for 20 meters, you can scale the loop for any amateur band between 160 and 10 meters, depending on the space available. If you want to use the delta loop for HF bands above 20 meters (12, 15, 17, and 10 meters), replace the coaxial cable and Q-Matching Section with 450 ohm ladder line and a balanced tuner. Delta Loops are excellent antennas for home or portable use. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can find more Amateur Radio news at my two news sites: http://kh6…

Simple Ham Radio Antennas--Ham Radio Satellite Arrow Antenna. Post #414.

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If you're new to Amateur Radio satellite communications, then this classic video by Randy Hall (K7AGE) is for you. Randy explains what the antenna is, where to buy it, and how to mount it on a simple camera tripod. I have a friend who uses this antenna for ham radio satellite contacts and it works quite well. Even a basic HT will get you many contacts with this antenna. According to the hams who use this antenna, it is easy to assemble and break down and makes a good portable antenna for field day or special event stations. The Arrow antenna is a quality product that should serve you many years. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. For more Amateur Radio news, please visit my two Amateur Radio news sites: http://kh6jrm.net and http://www.myalltop.com/KH6JRM. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today!…

Simple Ham Radio Antennas--10/15/20m Trap Vertical Antenna, Part 4 of 4. Post #413.

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Here's the final segment of Dave Tadlock's (KG0ZZ) excellent tutorial on how to build a 10/15/20 meter trap vertical antenna. In this video, Dave finishes his 20 meter and 40 meter traps, assembles the vertical, and runs a few tests of the newly-made antenna. Responders to this series say this trap vertical works well. The video is well-produced and logically organized. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--10/15/20m Trap Vertical Antenna, Part 3 of 4. Post #412.

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Dave Turlock (KG0ZZ) continues his tutorial on how to build a 10, 15, and 20 meter Trap Vertical Antenna. In part 3, Dave shows us how to build a 15 meter trap for the antenna. You can use a trap calculator to figure out the measurements. In part 4, Dave makes traps for 20 meters and 40 meters and finishes the final touches on this 3-band HF antenna. For the latest Amateur Radio news and events, be sure to check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us! Aloha es 73 de Russ (KH6JRM).

Note:  If you have difficulty viewing this video, please insert this URL into your browser:
https://youtu.be/1Ff4_4T9RiI.

Simple Ham Radio Antennas--10/15/20m Trap Vertical Antenna, Part 2 of 4. Post #411,

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Dave Tadlock (KG0ZZ) continues his discussion on how to build a trap vertical antenna covering the 10/15/20 meter Amateur Radio bands. In part 2, Dave shows you how to adapt the coaxial cable trap to the aluminum tubing. Please be advised that aluminum tubing may be expensive in your area. Check metal recyclers, a scrap metal dealer, or a plumbing repair business for scrap aluminum tubing. With a little care and a few tools, you can make low power traps out of coaxial cable and door knob capacitors. Like aluminum tubing, door knob capacitors may be a bit expensive. You may find these capacitors at Fair Radio Sales in Lima, Ohio. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--10/15/20m Trap Vertical Antenna, Part 1 of 4. Post #410

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If you have some time on a long weekend, you may want to try this interesting 3-band trap vertical from Dave Turlock (KG0ZZ). The antenna covers 20, 15, and 10 meters. Most of the materials can be found at your local hardware or building supply store. In part 1, Dave Also includes how to tune coaxial traps using the MFJ grid dip meter. This is a nicely crafted antenna that will bring you hours of fun on the upper HF bands. Dave has more information on programs 2,3, and 4. Stay tuned. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated frequently. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. If you have trouble viewing this video, please enter this URL in your browser:  https://youtu.be/SKcGN0P1Xjs.  Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Amateur Radio - Full Version (Discovering Amateur Radio). Post #409.

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A beautifully produced introduction to the world of Amateur Radio written and narrated by K1AN. This video was made for UNESCO and the World Genesis Foundation. The video discusses the many possibilities Amateur Radio offers for learning, safety, security, and emergency communications. The video takes us through a brief history of communications technology and then into the many exciting opportunities that the world of Amateur Radio offers. This video would make an effective prelude to a formal Amateur Radio Licensing class. I enjoyed this video. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. If you have difficulty viewing this video, please insert the following URL into your web browser: https://youtu.be/ivUMIADFSDw. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--Dipole Center-Loaded with Ladder Line. Post #408.

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An excellent tutorial on center loaded dipole antennas fed with ladder line from Stan Gibilisco (W1GV). He begins with a simple explanation of a center fed dipole fed with coaxial cable and then transitions to the same antenna fed with ladder line. If you cut your dipole for the lowest frequency of choice, say somewhere in the 40 meter band, and feed the antenna with ladder line into a balanced tuner (or through a 4:1 balun into your regular "tuner"), you could use the antenna for any amateur radio frequency from 40 meters through 10 meters. If you feed the dipole with coaxial cable, you would have a mono band antenna which could be used on the third harmonic of the fundamental frequency. A properly designed 40 meter antenna cut for the lower portion of the 40 meter band would do fairly well in the SSB portion of 15 meters. But, for other bands, the coax-fed dipole antenna would experience high SWR. This antenna is simple to build, erect, and use. For the latest Amateu…

Simple Ham Radio Antennas--Rattail Antenna Booster & Emergency Communication. Post #407

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Nice video by inventor Ian Soutar on the "Rattail Antenna Booster & Emergency Communication." Soutar claims the small pocket-sized device will double the range of your 2 meter VHF handheld transceiver. Soutar says the Booster "makes a capacitive coupling to the radio that has a low resistance." The device shares certain characteristics with what some Amateur Radio operators call a "Tiger Tail Antenna." This type of antenna is a quarter wavelength wire cut for 2 meters and attached at the base of the stock "Rubber Duckie" antenna that came with your HT. The "Tiger Tail" supplies the missing half of the vertical antenna and makes the stock antenna more efficient. The "Rattail Antenna Booster" works in a similar fashion. The "Rattail Antenna Booster" was invented by Ian Soutar, Ed Haslam, Barbara Soutar, and Jim Rawlings of Vancouver Island, British Columbia, Canada. The cost of the "Rattail Antenna B…

Simple Ham Radio Antennas--Six Meter Folded Dipole Antenna. Post #406.

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If you have difficulty viewing this video, please enter the title link into your browser search bar: https://youtu.be/qbje13U6hC4. Here's a fairly simple antenna project that will get you on the exciting 6 meter Amateur Radio band. The video tutorial by Claude Jollet is clear, well-produced, and easy to follow. Jollet says his 6 meter folded dipole antenna is "made of ladder line; the feed line is ladder line; and (is) matched with a step down 4:1 coaxial balun at the bottom of the transmission line." He says the antenna is cut to resonate at 50.4 MHz and shows a SWR of 1.3 to 1.0 between 50.0 MHz and 51.0 MHz. Good luck on "The Magic Band." For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).

Simple Ham Radio Antennas--40 Meter Dipole.wmv. Post #405.

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A basic, simple dipole that will get you on the air quickly. As commenters have mentioned, cut the antenna a bit longer for each element (2) to allow for trimming and SWR adjustment. If you want to use this antenna for both 40 and 15 meters without adding outrigger sections, cut the 40 meter elements for the low CW frequencies and the antenna will work on the third harmonic for the SSB portion of 15 meters. Most antenna transmatches ("tuners") will be able to handle the small mismatch in the antenna for each band. When I built one of these antennas, I cut the 40 meter portion for 7.088 Mhz (the Hawaii Afternoon net frequency). The antenna was pretty well matched at 21.264 MHz in the SSB part of the 15 meter band. Of course, you could cut the antenna for 40 meters and feed the dipole with 450 ohm ladder line into a 4:1 balun and then into your antenna tuner for coverage between 40 and 10 meters. Either way, the basic 40 meter dipole is a nice performer if you can get i…

Simple Ham Radio Antennas--Directional Antennas with Diana Eng. Post #404.

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An excellent tutorial on the simple physics of a Yagi Antenna from Electrical Engineer Diana Eng. Her use of a lightbulb to to show the effect of reflectors and directors on a dipole antenna is especially good. Although the video is a bit dated (03 February 2010), the basic information is still good. This video would make an excellent introduction to directional antennas for a Technician Class License workshop. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM.

Simple Ham Radio Antennas--Water's Edge Portable DX: A half square antenna on 14 MHz. Post #403.

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Well-produced video by Peter (VK3YE) on how to build a simple, effective, and portable half square antenna for the 20 meter Amateur Radio Band. Back in August, 2013, I described a similar antenna at a home I was remodeling in the Puna District (12 August 2013, Post #220). Although my half square worked very well, it wasn't as simple or as portable as Peter's design. Peter's antenna can be built with locally made materials from the nearest hardware store or home improvement outlet. In Peter's words, the half square antenna for 14 MHz comprises "a wavelength of wire bent into an inverted U. The half square over a good ground can radiate a low angle signal suitable for distant HF contacts. Construction is simple. Just take 22 meters of wire (72.16 feet) and string it up on two poles 11 meters (36 feet) apart, with equal lengths hanging down. Connect one to a coupler and load it against a counterpoise wire(s)." The antenna pattern is broadside to the half…

Simple Ham Radio Antennas--Tilted Terminated Folded Dipole. Post #402.

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Well-produced video from "Spectre Oz" on the rarely used Tilted Terminated Folded Dipole Antenna. In the author's own words, "A T2FD antenna project from design to installation, featuring 10w terminating resistor constructed out of 4, 5w 390 Ohm resistors in series parallel configuration and encapsulated balun/resistor for added overall structural integrity." The antenna can be used on a broad range of frequencies. This would make an excellent 10 meter antenna project for the weekend. For the latest Amateur Radio news and events, please check out the blog sidebar. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM). KH6JRM's Amateur Radio Antenna Topics.

Amateur Radio “EduTeam” Wows the Crowds at Georgia Super STEM Event. Post #401.

Amateur Radio “EduTeam” Wows the Crowds at Georgia Super STEM Event: Amateur Radio “EduTeam” Wows the Crowds at Georgia Super STEM Event.   Members of the North Fulton Amateur Radio League (NFARL) EduTeam in Fulton County, Georgia, offered students and other members of the public an opportunity to experience ham radio. The EduTeam hosted an Amateur Radio booth at the Sandy Springs Education Force’s Super STEM (Science, Technology, Engineering, Math) Event March 5 at North Springs Charter High School.  “The theme of this year’s STEM Event was Communications Technology, so we were a perfect fit,” said Martha Muir, W4MSA. “Waves of the North Springs students flooded our booth from the morning until early afternoon. Then it was time for students from the local middle schools.”

That evening, Muir said, officials from the Sandy Springs Education Force as well as other members of the community visited.

“Our booth was busy all day, tantalizing and educating our visitors with various aspects o…