Unfortunately there appears to be a bug in the formula for the position of the

first director in the 4-element model: this calculator puts it about 50% further

away from the driven element that W4RNL's original formulas.

In fact, the value given by the calculator for the distance between the driven element

and the first director is actually the

*reflector* to first director spacing. I just

verified this against the original spreadsheet.

With that change the values from the calculator should give good results: I've been

able to simply cut the elements to length and get the expected results with no tuning.