- Like many fellow radio amateurs, I own a fairly standard shortwave radio station consisting of a 100W HF transceiver driving a 1kW tube power amplifier. I never chose to spend any money on a kW-rated antenna-tuner. Anyhow, I can tune out VSWRs as high as 3÷1 with the adjustable pi-network of the output filter tank inside my power amplifier.
Thus I set out to design an HF antenna with a VSWR of 3÷1, or less, over the full bandwidth of as many amateur radio HF bands as possible. At the same time, my preference went out to the low- and the non-WARC bands. This design exercise resulted in a new kind of antenna which I dubbed Center-Loaded Off-Center-Fed Dipole Antenna, or CL-OCFD for short.
- In proof of its performance, an EZNEC-calculated VSWR-graph of the CL-OCFD antenna is presented in Figure 2. This antenna works without a tuner over the entire bandwidth of the 80, 40, 30, 20, 15 and 10m-band, simply by adjusting the output-tank of your tube power amplifier. —If your final output stage is a transistor amplifier, you definitely will need an antenna-tuner though.— In such, this antenna is the first described single-wire antenna to be offering these capabilities.
See Full Article: Link
In this video, I will show you how I interfaced my 7100 with the Mobilinkd bluetooth TNC wireless to my PC to send emails on 144Mhz Read more
HF/6m linear amplifier 2400W MRF1K50H 2 pcs water cooling system 5″ LCD touch screen for N0JSN Read more
The STARWAVES DRM SoftRadio allows you to conveniently enjoy any DRM live radio broadcast on your Android smartphone or tablet. No Internet connection... Read more
Description The fun and efficient way of learning morse code! Features: – Uses Koch’s training method (the most efficient known to date)... Read more
FlexRadio Systems and Marcus Roskosch, DL8MRE announced today a partnership to develop, market and sell a client interface application for both iPad®... Read more
Power Genius XL Searching for the highest performing solid state linear amplifier on the market today? If so, then the Power Genius XL (PGXL) amplifie... Read more