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( ) Cut a 3-1/2”(88mm)pieceofblackwireand
stripbothends1/4”.Attachandsolderoneendto
terminal N of the power entry jack. Attach and
solder the other end to terminal 2 of the power
transformer.
Twisted pair wire
()Beginbycuttingtwo30”(75cm)lengthsofwire,onered,oneblack,andtwistingthemtogether.
This can be done by hand, but it is most easily accomplished by clamping one end of the pair of
wires to the workbench (or having an assistant hold the ends in a pair of pliers), and securing the
other end of the pair in a drill chuck. Running the drill will spin the wires into a very even twisted pair.
The theoretical optimum is three turns per inch. The wire will shorten as it is twisted. Make sure that
thefinishedlengthofthetwistedpairisatleast24”(60cm).
Heater wiring
The tube heaters are powered
from the 6.3VAC secondary
winding of the power
transformer. The octal and
nine pin heater pins are wired
in parallel.
()Cuta5”(125mm)pieceof
the twisted pair, strip all ends
back 1/4” (6mm). Attach but
do not solder one red wire
end to power transformer
terminal 4. Attach and solder
the matching black wire end
to power transformer terminal
5. At the other end of the
twisted pair attach but do not
solder the red wire to B8L and
attach but do not solder the
black wire to B7L.
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