W8EMV - Whiskey Eight Echo Mike Victor: Antenna

On order: "Rothammels Antenna Book" from DARC Verlag GmbH

Rothammels Antenna Book is available in a first English edition, translating from the 13th German edition. I have it on order from https://rothammel.com/Rothammels-Antenna-Book and look forward to opening up a copy and seeing what there is to see.

My current antenna placement is that I have either a home attic to put wires in, or a bicycle saddlebag to carry a portable antenna, or my backpack to carry an HT plus whatever makes the reception and transmission best when carried on my back.

Some reviews:

Juan, posting to DX Engineering which sold copies at one point (not in stock): "This is a 1,600 [page] treatise on Antennas! It is more theoretical than the ARRL Antenna Book, but quite less than John Kraus classical textbook. It has a ton of data and practical information. It is a very good comprehensive reference book on antennas"

Frank K4FMH on https://www.amateurradio.com/rothamels-antenna-book-an-authoritative-source/: "I was researching HF loop antennas for an article. I was thrilled at the depth of coverage and the detailed citations and patents included. It greatly helped me organize my thinking on how to improve the design and deployment of an HF horizontal loop antenna."

Alex KR1ST on mastodon.radio , https://mastodon.radio/@kr1st/111794722432508536 "That is one of the best gifts you could have given yourself!! I have the German version and it's my go-to book on antennas. There are antennas in that book that many folks have never heard of and I have never seen described anywhere else."

Based on the size of the book this is a desk reference and not a handbook. Given the number of times I have done counterproductive things with antennas I am very much looking forward to absorbing some good sense and intuition and understanding.

Posted at 05:29 PM in Antenna, Books | Permalink | Comments (0)

KiwiSDR sites with Beverage antennas

A Beverage antenna is a long horizontal wire antenna pointed in the direction of the signals that are intended to be received. Patented in 1921, it was used for transatlantic reception of radiotelegraphy signals with antennas of up to 9 miles long. Of course not everyone has 9 miles worth of real estate (or for that matter 9 miles worth of wire), but there are contemporary receive antennas of the Beverage design used to good effect on KiwiSDR receivers.

Bob NH6XO has a 220 foot long Beverage antenna on his KiwiSDR in Hawaii. He writes on QRZ:

The Beverage antenna is made of about 220 feet of insulated #12 solid copper installed an “average” height of 6 feet. The Beverage antenna orientation is approximately 190 degrees true. For what it is worth, the Koolau Mountain Range blocks most signals from the West. As my interest is North America and Europe, leaving the antenna unterminated allows it to work well to the North and East.

W3HFU has several KiwiSDR systems set up, including one with a 500 foot Beverage antenna pointed towards Europe from his location in Maryland.

I live in a low noise rural area, and have lots of antennas :)

The "Pembleton Farm" KiwiSDR, located north of Ann Arbor, MI in Northfield Township, has a 230 meter / 750 foot Beverage antenna, pointed to the north. This is the closest SDR to my location, and it routinely gives me better reception results than any antenna I've been able to put up at home.

I haven't found an easy way to search the KiwiSDR database by antenna type, and if the operator doesn't include the antenna in the description it can be catch as catch can. One that I haven't tried yet but that looks promising is the VE6WZ Beverage array in Alberta - it promises 15 wires covering 9 directions from the Canadian prairie. Lots more details of construction and design on the VE6WZ QRZ page, almost 4 km of wire all told!

Why do these Beverage antennas work so well? It's a good design for long distance directional reception, and has been known for that for a very long time (100+ years). These antennas tend to get installed in low noise rural environments because where else can you get enough real estate to put them in? And perhaps most important, if you see a 500 foot antenna in active use you know that someone has made an investment in the hobby, and you really can't count on that for every KiwiSDR out there on the net.

Posted at 01:25 AM in Antenna, KIwiSDR | Permalink | Comments (0)

Operating notes: Nagoya NA-771 antenna, Washtenaw Skywarn

The stock antenna on my Baofeng UV-5R stopped working just before a vacation trip up north. This got in the way of operating in the Upper Peninsula, which I had been looking forward to. Oh well, several the repeaters up there have Echolink, so any time I want to tune in I can, as long as I have wifi or cell data coverage. I didn't go on the air while I was there, though I did monitor one conversation (about snowmobiling).

I've replaced the Baofeng's antenna with a Nagoya NA-771. It's quite a bit longer than the original equipment, so much so that it just barely fits in my bookbag. It still does fit, though, and that means I can still carry a radio around with me anywhere. I haven't done exhaustive trials of performance but it's clearly better that I had been getting before, and overall I'm happy with the switch to a new antenna.

It was a busy night tonight on the N8DUY 145.15 repeater as storms blew through the area causing widespread power outages and lots of talk on the Skywarn net. Even though there was a lot of static, I still was able to hear the talk on the air and relay reports from trained spotters to Twitter. (I'm not a trained spotter yet - yet! - so I didn't check in to the net.)