To All from PA0SE,
Many thanks to Walter Blanchard for the interesting info on the Puckeridge
Decca station aerial.
four
booms were taken off altogether and the 3750 pf capacitance restored by
running eight
wires from the top down to a new set of insulators spaced 50 ft frm the
mast.
Capacitance had to be kept at 3750 pf because the loading coils had been
designed
for this and couldn't be altered - too expensive!
Interesting that this way of maintaining the capacitance was adopted instead
of simply putting an extra capacitor in parallel with the aerial. Can it be
that the cost of the extra wires plus insulators plus anchors for the
insulators was lower than the price of a capacitor?
73, Dick, PA0SE
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