high-level accessory front end for the HF amateur bands

Posted on Feb 6, 2014

Here`s an antenna selector, Preselector, attenuator, preamplifier accessory for every HF amateur transceiver. It can improve your receiver`s IP2 for out-of-band signals and yield good flexibility. My father, I4FAF (an old-timer) and I both very much like Amateur Radio as a lifetime endeavor. We do not have backgrounds in electronic engineering,

high-level accessory front end for the HF amateur bands

Click here to download the full size of the above Circuit.

but we do have a lot of practice. My father is a fast builder ofAmateur Radio projects, from printed-circuit artwork drawn by him with CAD software to working units in our home laboratory. Being retired now, he has more time and I help him from time to time. Our goal is to get more from the Amateur Radio equipment available to us. Our gear is average, not toppriced. I want to improve my skills with DX or weak signals, while I operate in crowded bands during some international contests. Lately, I have discovered the low-frequency bands. They have added more fun. In 2000, we started to put up (at a flat, country location) a short vertical antenna by Butternut, the HF2V It has the 160-meter coil kit, is top-loaded with four wires (each about 5 meters long) and has six ground radials about 40 meters long for 160, 80 and 40 meters. In winter 2001/2002, we started to test some receive-only antennas, with better signal-to-noise ratios and some directivity, in comparison to the 360 ° radiation pattern of a vertical antenna. With the exception of Beverage and a four short vertical system presented by W8JI on his Web site, that still require much space for only -6 to -11dBi; most of the receive-only antennas we have considered are in the low-output category-in the range from -6 to -35 dBi. We have worked with Beverages, EWE, the delta-EWE by K6SE -a variation of pennant-flag antennas and K9AY loops. We have seen them presented by...

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