43 Foot Vertical Pops a U-Bolt

The top U Bolt holds while the bottom just hangs there.

Another title might be… “43 Foot Antenna, the Tilting.”

NOTE: UPDATE AT END OF THIS POST

We had a big blast of cold air come down from Canada last night. Temperatures reached the teens and winds peaked at 50 mph. No problem I thought… “My DX Engineering 43 Foot Vertical has been up in weather like this since 2008 and does exceptionally well.”

The morning was busy gathering up blown away things and mounting a search and rescue of my car cover. Often this car cover sweeps around the house so I walked out back.

My eyes scanned the back yard for the cover. HORROR! I looked up to see a not so vertical antenna against the December backdrop of a cornfield and morning sky. Figure 1 reveals my shock and awe moment…

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Dallas Cowboys, DTV, Wife and Hex Beams

So what do the Dallas Cowboys, Digital Television over the air broadcasts, my wife and the Hex Beam have in common…

You’re probably thinking…

“Man… John has lost it. He’s blogged one post too far… On Halloween afternoon too…”

Hang with me for a moment.

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Dipole Generates Static in PL-259

Irrespective of the fact the solder-the-braid PL-259 connector is probably the worst RF connector conceived by the mind of man1 and the fact the spark shown in the video is in an area that should be a direct short, the video, shown below, wonderfully shows the ease with which static charge can build on a dipole antenna.

That’s not the point though. If we were to cut off the connector we would surely still see a spark from center conductor to shield. If the cable were near station ground we would expect a spark jump. That large a charge has to go somewhere.

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Magnetic Mount Antennas Don’t Suck

Mag Mounts. Bum Rap?

Over the years I have heard amateur radio folks, CBers and scanner fans bash the use of magnetic mount antennas. Concerns include flying off the vehicle and becoming a projectile during an auto accident. Other concerns relate to performance and stem primarily on how well the shield of the coax is electrically connected to the conductive body of the car.

I cannot comment on the mechanical realities of the antenna flying off the roof during rapid changes in speed, but can say I have never seen one do so. I encourage anyone with data to propose their article to this web site

So…

Addressing the Mag Mount Electrical Questions

Let’s talk about the electrical conductivity of a standard mount vs. a magnetic mount antenna. Here is a quote from the newsgroups concerning antennas for scanners…

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Elecraft K2 – My Favorite Field Day Station

This year our club ran 3A for the ARRL Field Day.

Radios included an Icom IC-756 Pro, TenTec Omni VII, Icom IC-746 (for the GOTA) and a Icom 7000 for VHF plus HF spare. All these radios performed quite well despite the high temperatures.

The 100 Watt Elecraft K2 stood above the others not necessarily on performance, but the elegant way the radio’s owner configured his K2, 100 Watt Amplifier and 100 Watt Matcher.

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Field Day Prep

Well Field Day 2010 all started to come together pretty well. I put all the drinks and heavy items in the front to ensure good positive tongue weight. Pre-positioned the radio on that beautiful desk. Loaded up several antennas. Three masts plus stakes, etc. I even managed to figure out how to get my hex beam in there with a minimum of dis-assembly. It is quite a mess. I am sooo glad I selected that slinky wire that does not kink.

Here is a picture.

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Assateague Lighthouse Repeater Antenna?

There is nothing like going to the beach.

Seafood, sand in everything you own, beach strolls, a time with family away from the usual distractions of life.

What better to do at the beach than visit the local lighthouse… especially a big coastal light station like Assateague Lighthouse on the Eastern Shore of Virginia.

Of course being a ham makes you notice things others miss with your “hammy eyes.”

Follow along in this picture tour of our visit to Assateague Lighthouse in 2007 and see the unusual thing we found within.

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Small Loop HF Mobile

In the never ending quest to improve our HF mobile ops for the Virginia QSO Party we finally decided to try a small loop.

There is nothing new about small loop antennas. They have been discussed in the literature for decades. The ARRL has some very old articles about them in the 1968 March and July editions.

Constantine A. Balanis’ book on Antenna Theory discusses and defines large vs. small loops. This book is an essential reference if you seek the details on how loops work. The loop described below fits into the “small loop” category where the currents along the conductor are, for all practical purposes, constant. This is unlike full size antennas where current reaches a minimum where voltage approaches maximum. Since this loop is electrically short with respect to wavelength, current does not change “much.”

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Good Source of Crimp PL-259 for 0.4″ Coax Cables

A few years ago I installed lengths of LMR-400 Direct Burial coaxial cable in my back yard. I wanted good connectors for my investment. I seriously considered the superior N connectors, but my DX Engineering Coax Switch uses SO-239 connectors. While not the high quality choice, I succumbed to tradition and sought out suppliers for the PL-259.

Money was really no object since the connector is often the weak link in the system and deserves quality. I just made an investment in 240 feet of LMR-400 cable and wasn’t about to shortchange the connector.

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Whacker in NC

Another possible Whacker runs afoul of the law.. or did he.

ARRL Emergency Communications Handbook – First Look

My latest ARRL renewal came with the usual free gift. This time I selected the “Emergency Communication Handbook.” I made a promise to the fifteen or so EmComm organizations that made an appearance during the Haiti tragedy to look at EmComm again with an open eye resulting in the ordering of this book.

Fair enough.

I was glad to order this book to see how EmComm might be done from a well organized perspective. I sat down one evening and opened it up. Here is the first sentence…

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