The short and linear FCP was designed to reduce ground losses from inadequate radial systems beneath inverted L's and other vertical antennas. The FCP and Isolation Transformer allow us to get on Top Band and do well from a small building lot and other restrained circumstances. Other loss issues may be found and eliminated. We begin with the FCP, and then introduce the Pandora's Box of Loss Issues below.
Before the FCP was published in 2012, W0UCE laid out this drawing of the FCP. Tried and true, it has quickly explained the FCP ever since. Some looked at this drawing once and went out and built it. And it worked. So we have placed it in our opening screen.
The drawing has had only minor changes since 2012, also adding
Please do not consult the "The FCP Story" (Original NCJ magazine article PDF), "The Wayback Machine" or older cached/archived/printed versions of this web site for construction and technical information on the FCP and low band RF loss mitigation. Use k2av.com directly so you have all the new and updated technical content. The version you are viewing is at the bottom of the green index buttons. This web site went on line September 2017.
to the Single Drawing FCP Description:
(a) The ±33 feet (±10m) above is for 160m. For 80m use ±16.5 feet (±5m). For 60m use ±11.2 feet (±3.4m). For 40m use ±8.2 feet (±2.5m). Use 4 inch (100 mm) wire spacing on 160, 80, 60 and 40m.
After Jack's FCP drawing and basic construction text, the rest of the FCP-related web site content exists because implementing FCP's exposed a Pandora's Box of RF loss Issues. Notably, eight green button topics treat inverted L issues. Remedying or designing around those losses exposed still more issues. "FCP+" is what we call a project that installs an FCP and remedies any other loss issues. RF Loss issues are treated in .
The "Plus" items are not required to make an FCP work. They just remove loss. The total loss remedy from a fistful of fraction of dB issues can exceed the major remedy of the FCP itself. FCP+ sometimes produces an amplifier's increase in TX signal strength without the amplifier.
At a particular ham station, which RF loss issues actually exist varies wildly. RF Loss remedies, in individual stations with their individual situations, can range from easy to impossible. Issues are not in the list because we are convinced they exist at your station. We list them because the individual issues have existed and have been remedied at multiple FCP project sites. Any issue might exist and be fixable at your site. Certain issues have proven common, with a select few more likely present than not.
Reading while planning a station makes very best use of the Loss List, avoiding RF losses in the first place.
You can read the story leading up to Jack's drawing in the first four columns of the original May/June 2012 NCJ article. Note that portions of the article's technical content are no longer current. **Please use the web site you are viewing now for all technical content and direction.**
Are you using an FCP? If so drop us an email at peerreview[at]k2av[dot]com and let us know about it and how you are doing. 73, The Committee.
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Balun Designs™ is a highly valued commercial resource, providing a source of professionally constructed transformers described on this web site. However, Balun Designs is not responsible for the design of said transformers, and not responsible for explaining how to use them. Balun Designs warrants their workmanship and that the 1142s uses the same design and materials specified on this web site for those winding their own transformers.