Coat Hanger HDTV Antenna. Post #4480


This oldie but goodie is great for those of us who don’t want to spend a lot of money to get HDTV reception.  I built one of these a while back for my occasional tv viewing (PBS and news specials).  Ron Voorhees uses common materials available in your shack or at the nearest hardware store.  There are more sophisticated designs on the internet, but, for my purposes, Ron’s approach is simple, inexpensive, and fun to build.  Aloha de Russ (KH6JRM).

Dipole and Inverted V Antenna Basics


One of the first antennas I rebuilt after the passing of Tropical Storm Iselle (o7-08 August 2014) was my trusty 80-10 meter inverted v.  The previous inverted v was torn up badly by 60-65 mph winds from the storm.  I managed to salvage most of the 450 ohm ladder line and a good portion of the antenna segments.  While I was researching for better ways to “harden” my wire antennas, I came across this helpful article by Dave Tadlock on the construction, mounting, and tuning of dipole and inverted v antennas.  While I incorporated much of Dave’s ideas, I elected to keep the inverted v as a multiband antenna, covering 80 through 10 meters.  With 450 ohm ladder line fed into a 4:1 current balun and using a short length of RG-8X coax to connect the balun to my trusty Drake MN-4 transmatch or the standby MFJ 941-E Versa Tuner II, I had an antenna capable of serving these amateur radio bands.  Each antenna element was 67-feet/20.42 meters long, giving me resonance at approximately 3.500 MHz.  With the ladder line, balun, and transmatch combination, I was able to get a 1:1 SWR on all amateur radio bands between 80 and 10 meters.  Dave’s video is well organized and loaded with many valuable hints.

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Until next time,

Aloha de Russ (KH6JRM).

How to Build a Delta Loop Antenna.


A quick guide to building a simple delta loop antenna for 20 meters.

(http://www.youtube.com/watch?v=QJl359x6K_1).

I came across this article and video while I was searching for loop antenna ideas at my QTH.  Excellent presentation by Hiram Vazquez (WV2H), covering how to build a 20-meter delta loop and how to make a simple Q match for the antenna.  The Q match will make the antenna resonant at 50 ohms at the feedpoint.  According to Vazquez, the delta loop is bidirectional, offers some gain over a dipole (about 1.2 dB), is easy to build, and is inexpensive. Vazquez built his 20 meter delta loop in March 2012 and has worked 215 DXCC stations, with 100 watts.  This looks like a simple, effective antenna for your backyard.  I’ve used delta loops in the past and have found them quiet and easy to tune.  To obtain multiband use, use 300 ohm tv twin lead or 450 ohm ladder line into a balanced tuner.  If you lack a balanced tuner, feed the ladder line into a 4:1 balun and run a short length of 50 ohm coaxial cable from the balun to your antenna transmatch (tuner).  Aloha de Russ (KH6JRM).

See on Scoop.itKH6JRM’s Amateur Radio Blog

Simple Ham Radio Antennas. A 80-10 meter Inverted vee antenna. Post #287.


One of the easiest and most cost effective antennas you can build is the 80-10 meter inverted v, a variant of the HF Doublet (horizontal dipole).  The antenna requires a single support mast, two smaller poles to tie off the “drooping” elements, and 450 ohm ladder line/300 ohm television twin lead connected to a balanced “tuner” to work all amateur radio bands between 80 and 10 meters (3.500 MHz to 29.999 MHz).  If you don’t have a balanced “tuner”, run the ladder line or twinlead to a 4:1 current balun and use a short length of 50 ohm coaxial cable to connect the balun to your “tuner.”

During the course of moving into our new home in the Puna District of Hawaii Island (we’re moving slowly, since we’re still working part time), I found a nice spot for a mast in the middle of our planned garden in back of the garage.  Since our home is on 1 acre of agricultural land, I have plenty of room for antennas, including loops, slopers, verticals, horizontal dipoles, and the inverted v.

Materials:

One 33-ft/10.06 meters MFJ telescoping fiberglass mast.

One “Ladder Lock” connector to attach the ladder line to each antenna element.

75-ft/22.86 meters of 450 ohm ladder line.

Six feet of RG-8X coaxial cable with UHF connectors.

Two pvc support poles to tie off the drooping antenna elements. I had two, 10-ft/3.04 meters pieces of schedule 40, 2-inch/5.08 cm diameter pvc pipe sections in the garage.

Two ceramic end insulators to tie off the ends of the antenna elements.

One 5-ft/1.52 meters wooden stake to support the fiberglass mast.

Two 5-ft/1.52 meters wooden stakes to support the tie off posts for the inverted v.

One W9INN 4:1 balun.

One transceiver.  For this project, I used my trusty Ten-Tec Argosy II.

One Heathkit Dummy load.

One low-pass filter.

One Drake MN-4 antenna transmatch.

One “counterpoise bundle” for the Drake MN-4 transmatch.

Nylon ties and vinyl electrical tape.

Basic tools, including soldering iron, wire cutters, screwdrivers, etc.

One hundred 135-ft/41.15 meters of #12 AWG house wire.  I had a spool left over from a wiring project at the new house.  No sense wasting valuable copper.

Twenty-five ft/7.62 meters of nylon rope.

Assembly:

The antenna was built in the garage, because all of my tools and electrical outlets are located there.

The telescoping fiberglass mast was extended to its full length (33-ft/10.06 meters) and the “Ladder Lock” device was attached to the eyelet ring at the top of the mast.

The wire was cut to my chosen frequency of 3.500 MHz using the formula 468/f(MHz)=L(ft). According to the formula, the total length of the antenna would be 133.71-ft/40.76 meters. I rounded off the length to 134-ft/40.76 meters.  Each antenna segment would then be 67-ft/20.42 meters. You may want to cut your wire elements a bit longer to allow for swr adjustments.

I threaded the ladder line through the “Ladder Lock” and soldered each antenna segment to its respective leg of the ladder line. I covered the soldered joint with several layers of vinyl electrical tape.

At the free end of each antenna segment, I attached a ceramic insulator and a small piece of nylon rope to tie off the segment to a support post.

The ladder line was run down the fiberglass mast to a point 16-ft/4.87 meters above ground level. The ladder line was secured to the mast with nylon ties.

The mast was then hoisted onto its wooden stake with the two antenna elements being left free for the moment.

The free ends of the antenna elements were attached to their tie off posts (the 10-ft/3.04 meters pvc pipes). Each tie off post was hoisted into position.  The antenna was adjusted for a uniform “v” shape.

The ladder line was lead to the W9INN balun attached to the garage wall (about 8-ft/2.43 meters above ground level).  Ten feet/3.04 meters of RG-8X went from the balun to the window patch panel.  Inside the shack, a 6-ft/1.82 meters piece of RG-8X ran from the patch panel to the Drake MN-4 transmatch.  The Argosy II, dummy load, and the low pass filter were connected to the Drake MN-4 transmatch with 3-ft/0.91 meters lengths of RG-8X coaxial cable with UHF connectors.  Finally, a “counterpoise bundle” was attached to the ground lug of the Drake MN-4 transmatch.

Initial results:

With the Drake MN-4 in the line, I was able to get a 1:1 match on 80, 40, 30, 20, 15, and 10 meters.  I was running a full 50 watts from the Argosy II.  Results on 80, 40, 30, 20 and 15 meters were excellent with several 59 (SSB) and many 599 (CW) contacts made in Hawaii and on the U.S. mainland. The ten meter band was very noisy at my location and no contacts were made.  Eighty and Forty meters were best in the early evening hours, while 30, 20, and 15 were most usable during the early afternoon to early evening hours.

If you want a versatile, simple antenna that covers 80 through 10 meters, please consider the easily made inverted v.  If you have two high supports (trees, masts, or other structures), you might get a slightly better signal with a horizontal dipole erected at a height of 40 to 60 ft/12.19 to 18.29 meters above ground level.  Even though the apex of my mast was only 33-ft/10.06 meters above the ground, the antenna did very well on both local and DX stations.

This was an enjoyable antenna to build.  Give it a try…you might be surprised how well it works.

References:

http://www.arrl.org/hf-wire.
http://www.hamuniverse.com/htdoublet.html.
http://www.radioworks.com/nhpant.html.
http://www.dxzone.com/dx22153/80-40-20-meter-dipoleantenna.html.
http://www.balundesigns.com/OCFAntenna.pdf.

For updated amateur radio news and happenings, please check out the news feeds provided at the top of this post. These feeds are updated throughout the day.

You can follow our blog community with a free email subscription or by tapping into our blog RSS feed.

Until next time,

Russ Roberts (KH6JRM).

Baofeng UV-5R radio with Reviewing 5 Portable antennas comparison amateur radio 2 metres from M6DZZ


Stumpy SRH805S Flexi Stumpy SF20 Dual Band VHF/UHF 144MHz/430MHz Medium Flexi 5-152 ANTENNA 136-174/400-520MHZ Long Flexi Nagoya NA-771 Baofeng UV-5R radio…

Source: www.youtube.com

M6DZZ reviews five antennas that can be used with the Baofeng UV-5R HT.  These antennas are available from eBay.  As with any internet purchase check out the product and the seller before you buy.  Aloha de Russ (KH6JRM).

Ohio Antenna Law Challenge May Be Over: – eHam.net


See on Scoop.itKH6JRM’s Amateur Radio Blog

Ohio Antenna Law Challenge May Be Over: eHam.net In a surprise move, the Ohio Sixth District Court of Appeals https://www.co.lucas.oh.us/index.aspx?nid=171 has dismissed an appeal from the Village of Swanton, Ohio, in an Amateur Radio antenna

Russ Roberts‘s insight:

The Ohio Sixth District Court has dismissed an appeal from the Village of Swanton, Ohio, in a key Amateur Radio antenna zoning case.  In essence, the court ruled that federal and state law preempted Swanton’s antenna ordinance.  Gary Wadtke (WW8N) has tried since 2009 to build a 60-ft/18.29 meter “antenna support structure” on his property.  With the ruling Wadtke is free to finish his tower project.  However, opponents of antenna towers vow to return to court if a similar case comes up.  The message is clear:  be prepared to spend a lot of money for your tower (materials and attorney fees) if you live in an area that restricts “support structures.”  Some amateurs can’t afford to move to more “friendly” areas, so they must be creative in getting and staying on the air.  With the spread of HOAs and CC&Rs these days, one must become an expert at stealth antennas.  Remember, out of sight, out of mind.  Good luck.   Aloha de Russ (KH6JRM).

See on www.eham.net

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