N5ESE's 3-Bee (3-Band) Antenna Tuner


Sorry! Under Construction! but here's what we have so far...



I built this in preparartion for my portable outing during the 2003 Bumblebee Contest, but it didn't work as well as I had hoped. I was never sure whether it was the antenna which was unpredictable, or whether I wound one of the coils wrong. Just the same, I'll post it here so you can figure it out if you want, or try something similar.

The idea was to build a compact 3-band antenna tuner, in an Altoids tin (what else?), to be used with the original AT-Sprint, which covers 40/30/20 Meters. The tin would enclose three independent L-nets, and was intended to feed an 86 ft end-fed "Inverted L" wire, working against a counterpoise system consisting of two 1/4-wave radials on each band. The antenna system was modeled in EZ-NEC for Windows, and the results were used to calculate the predicted L-Net needed for a match. Here's the schematic:

Trimmers were to be adjusted in the field using a plastic tool, which is velcroed to the inside of the cover, along with a schematic to remind me what I was doing HI HI. Here' s a picture of the "guts" of the unit:



[Click on the above image to see a larger version]

Copyright 2005 ...[ view copyright info ]...
Overseer: Monty Northrup ... n5ese@prismnet.com ... leave e-mail ...

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