Tuesday, March 20, 2018

Antenna

Having an outdoor antenna mounted on a mast will make a big difference in how well you can hear as well as how far you can transmit and receive. In years gone by it was a right of passage into ham radio to build your own single band 2-meter antenna using 1/2" copper water pipe and fittings. They do a good job. They are fun to build, and they were probably the least expensive antenna we could find to start our ham radio journey. KD7RTR is still using hers. It is mounted on the brick chimney. Any plumbing vent pipe will suffice as a mount for a J-pole antenna.

We do have some other choices now that we can use. If you have the page on your computer you will see the choices.There are several commercially built antennas. N7OZH always recommended the Arrow aluminum J-pole antenna. You can see that on the blog page with the pictures. One picture shows one on my portable mast. I use one myself and I have another on my portable mast to go wherever needed.
A similar antenna is made here in Utah and buying locally will save you money.

Look for the magnet mount dual band antenna with the gold background. I have a Browning and a Tram brand. They are not much more expensive than the mini mag. The mini mag. does not last when used on a motor vehicle and is not repairable. Our handheld radios come equipped with what N7OZH referred to as a rubber attenuator. Others call them a rubber duckie.There are differing opinions as to however useful, or not, they may be. I have one radio with one and others using the Nagoya or Comet HT antennas. Find the picture of the SMA/SO239 pigtail. Not an antenna itself but a very useful addition to you go bag. I have one of these and its purpose is two-fold. I bought it to use on my SMA equipped handheld to relieve stress if I have to connect to RG-8 coax someplace. These are available with a few or up to 20" inches of thinner, more flexible coax to make handling the radio easier on you and your radio.

There are at least five of us that have an outdoor antenna at this time. I would ask that those who do not have an outside antenna put that on the list of things to do this year. 1 - J pole antenna, 1 - 20 ft length of chain link fence top rail that can be secured to your house, or other structure for support should do. That's what I am using. sufficient co-ax cable to reach from your antenna to your radio should be easy to do. It is expected that care and caution will be used to make your installation safe, and secure.

Grounding your mast, and antenna is both useful and important. There are many sources of information you can read. There are many people whose opinions you can listen to. I suggest you do your homework and determine which you will choose. N7OZH often told of sitting at his desk and hearing a crackling sound. He found that sparks were arcing from the center conductor of a PL-259 connector to the outer shell. It was not a stormy day but the wind was blowing. The friction of wind blowing past his antenna was generating static electricity sufficient to arc between the shield and the conductor. For safety, N7OZH lined a ceramic mug with aluminum foil that he said was grounded in his shack.

I, myself, have done things differently. My UHF-VHF aluminum J-pole antenna is mounted directly to a 20' steel mast. That is supported by a 6' galvanized steel post and is mounted in such a way as to have electrical continuity. Inside my shack, I use a grounding Coax switch. Pictured below. When the pointer on the knob is in the center, Your antenna coax is grounded. There are several grounding products and some lightning arrestors. I have no experience with those at all. Others have told me that if my station took a direct hit, I would definitely have damage. Maybe a Little. Maybe a lot. I have never yet had damage and certainly never a direct hit. Is it because I did something right, or is it because I have had good luck? I think it was some of each.

An upcoming event: The Utah Valley Amateur Radio Club is having a swap meet 29 Sep 18, 475 S Main St. Buying and selling to begin at 9:00 AM. Set up for sellers is 7:30 AM. $5., $10. family, $5. for seller's table.

KD7NKW - Richard











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