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2. Insert the fuse and cap assemblies into the power supply’s fuse holders. The
fuses lock in place with a quarter turn.
3. Connect the power supply to the amplifier.
4. Be sure the amplifier power switch is
off
.
Caution!
Fuses have both voltage and current ratings. Use only
250V rated fuses in this device. The voltage rating is generally
marked on fuses. DO NOT use automotive-type low voltage fuses in
any power line application. For 240-volt operation, 15-ampere fast
blow fuses are required.
Warning:
Never insert the power supply cord into the outlet until
you have completed the four steps above!
Position the amplifier at or near the desired location on your operating desk so you have
access to the rear panel, and connect the rear panel cables. Do not connect the power
mains at this time!
Safety and Lightning Grounding
The power supply cabinet grounds through a safety ground pin on the power plug. This
system depends on a properly wired power outlet.
Lightning protection grounds do very little good at the operating desk. Lightning
protection grounds belong at the antenna cable entrance to the building. Station ground
rods
must always
be electrically bonded, with low impedance and resistance, to the
power line entrance ground. The national electrical code in the USA prohibits isolated
ground systems at a dwelling entrance.
Isolated
ground rods or systems connected to
conductors entering a dwelling increase the chances of damage from storms, and
increase fire hazard and shock risk.
RF grounds generally belong at the antenna, or at the feed line entrance. With the
special exception of a small floating counterpoise grounds, RF grounds at or very near
the dwelling should bond into the mains ground outside the dwelling. This is especially
true with earth contact grounds.
There is a ground lug on the amplifier rear panel. This ground lug provides a convenient
chassis connection for operating positions with ground bus on the desk. A station
ground bus helps ensure desk area equipment cabinets are close to the same electrical
potential for radio frequencies and lower. Equipment ground lugs are
NOT
for
independent wires or connections to external ground rods or ground systems from each
piece of equipment. They are for connection to a desktop ground bus system, if you
prefer to use such a system. Independent wire connections are counterproductive, the
opposite of good practices.
Never use RF isolators between the amplifier and radio. Never use long independent
wires to external ground. Never connect desk equipment to ground rods that are not
bonded to the mains ground rod.
Station RF Ground
Common rumor is that a station equipment ground reduces RFI (radio frequency
interference), reduces lightning damage, or improves signal levels. Generally, changes
in RFI or signal quality, with the addition or removal of a station ground, indicate an
Summary of Contents for ALS-1406/S
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