These are two different kinds of wire.
WD1 is designed for the old tip and ring phone systems of the 40's-60's and
consists of two twisted seven conductor wires, three galvanized steel and
four tinned copper conductors.
WD1A came out in the 70's and is smaller and joined together like zip cord.
It has the same conductor combination as WD1.
They also have different impedances so their feedline matching is different.
Craig
Craig Clark K1QX
QX Electronics
PO Box 209
107 Fitzgerald Rd
Rindge NH 03461
(603) 899-6103 office
(603) 520 6577 cell
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Topband Reflector
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