A Google search has resulted in two sources for the indoor control box and
the outdoor direction-switching relay box used for the K9AY four direction
receiving loop antenna system.
WX0B offers the indoor control box and outdoor switching box and a separately
purchased termination resistor (fixed value). This system allows four
directions to be selected.
Wellbrook Communications in England offers the same two boxes but with some
interesting improvements (I presume these changes are in fact improvements).
The Wellbrook units incorporate a remote controlled variable termination
feature which apparently allows adjustment of the value of the outdoor
resistor to obtain the best result for the soil conditions at your location and
allows adjustment as your local soil conditions change as a result of rain,
Also the Wellbrook system incorporates what is described as a rotary beam
direction control which allows you to fine tune the favored direction for the
best result instead of having only 4 fixed directions for selection as used in
the original article by K9AY and used for the WX0B system.
So, has anyone used the Wellbrook system? Is the variable termination
feature worthwhile? Is the rotary direction control feature worthwhile or
The cost of the Wellbrook including shipping is about 300 British pounds
which is about $500 US depending on the pound/dollar exchange rate. This cost
quite a bit more than the price for the WX0B system.
All comments are welcomed. Thanks es 73
Jan Rehler, W5KNZ, Corpus Christi, Texas