Today, I learned about whole wave dipole antennas and their impedance problem; details I suspected about the novel The Natural; the nicest radio club I've come across so far, the North American QRP CW Club
Full-wave dipoles
First, lets talk about full-wave dipole antennas. Spoiler, do not run out and build one without reading to the end, I almost did. It turns out that while the things offer some gain, they have this impedance issue which is... infinite impedance at the feedpoint!!! In other words, oh my goodness will your power reflect back into your transmitter without a matching network.
Why was I reading about the cursed things? Well, that takes us to this ARRL article on QRP (From April 1984 QST, p 52). The article suggested that what I really wanted was a full wave dipole:
You know? If I had the resources to build an antenna tower, I'd probably also have resources and patience to build the impedance matching network so really it's a matter of resources that informs my perspectives on the full-wave dipole, and at the moment, I don't have them, so no full wave for me, and thank goodness I did the extra research so I didn't have to replace a transistor on the Rockmite.As I look into changing the antenna in the future, I'll be keeping this gain table from Wikipedia in mind:
I want to write about perspectives on QRP. There's more about that a little later. Anyway.
The Natural
The thing I suspected about The Natural by Bernard Malamud since I was a kid, namely that it's steeped in Arthurian Legend, was confirmend for me today by a self-help book of all things. (I share the sentiments of Leslie Kern when it comes to these in general.) Anway. The author of the book, The Creative Habit, Twyla Tharpe had it confirmed for her by an English professor... do I have their name???Nope. But here's a gem from the book: Pop Fisher is a reference to the Fisher King!!!
North American QRP CW Club
And finally, I discovered today that I'm already a member of this club. In general, I'm not a radio contesting person. I operate QRPp (less than 1 watt output power from the Rockmite), and I get completely washed out by contests which seem to splay across the QRP sections of the radio bands as well. What does that mean? Big stations with tower antennas running 100s of Watts. Yikes. No one can hear the Rockmite in comparison to that. Sooooo, it was really nice to see this on the QRP club's FAQ:
A half-wave dipole at sunrise on the the San Francisco Bay.
Which! The gang and I did antenna work yesterday! Anyway.
References
The book where I found the Roy Hobbes references. (Snort! When I went to the publishers website for the book, I received a free week of Pimsleur language programs, the CD series that's cringingly about how to get a date in many different langauges.)
More about the NAQCC:
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