the Hafler transformers are designed to minimize this field,
certain cartridges are more sensitive than others, and
require separation from the amplifier. Check at a compara-
tively high volume setting, swinging the tone arm through
its arc. Usually a few inches of added space is all that is
needed.
Line Connections and Switching
The SE-240 is normally wired for use on 120V AC power
lines, as in the USA. If your line voltage is different, you will
need the special Hafler export power transformer which
accommodates many other line voltages. Be sure your
amplifier is wired for your line voltage before you plug it in.
The SE-2403 power switch may be left on, and the
amplifier switched remotely by connecting its line cord to
a preamplifier (or other control center) which provides a
switched AC outlet. Make sure that the control device can
supply a current of 10 amperes to the SE-240, in addition
to the current required by any other switched units. You
may instead connect the amplifier directly to a wall outlet,
and control it with its own front panel power switch.
Connecting Cables
INPUT
. Conventional shielded cables, often supplied with
preamplifiers, may connect the control center to the
amplifier’s input jacks, Be sure the cables are not frayed
or loosely connected to the plugs, and that the plugs outer
shield connection is tight on the jack, to avoid hum. If you
wish to install the SE-240 more than a few feet from the
preamplifier, the permissible cable length to avoid loss of
high frequencies is determined by the preamplifier’s output
impedance and the internal capacitance of the cable. If the
output impedance is 600 ohms or less, as with Hafler
preamplifiers, and the cable capacitance is less than 50
picofarads per foot, up to 50 feet is acceptable. Ordinary
stereo interconnecting cables often have higher
capacitance, however, so a good quality low capacitance
shielded wire should be used. When making long runs,
keep the left and right cables close together, and avoid
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