The HD-73 rotor incorporates all features that contribute to
strength, durability and ease of installation
without special tools or equipment as well as simple
foolproof operation of the control box.
The HD-73 rotator is constructed of heavy duty aluminum
castings selected for their excellent strength
capability and favorable weight characteristic, contributing
to ease of erection and resistance to severe
wind and adverse weather conditions that exist throughout
The HD-73 unit is factory lubricated with a lifetime high
quality lubricant that will withstand temperature
ranges of 120° Fahrenheit to —20° Fahrenheit.
The HD-73 mast support bracket design permits a centering
procedure for in-tower application without
shims or difficult trial and error adjustments and the base
design permits easy four bolt in-tower mounting
without spacers. The mast support bracket design also
provides a positive drive no-slip option.
The HD-73 rotator unit has two full raceways of 100 ball
bearings which give it excellent balanced
weight bearing capacity.
The HD-73 has an improved automatic brake action for
simplified operating procedure which also reduces
risk of antenna damage by sudden stops imposing high inertia
stresses on the antenna, tower and
The i iD-73 has the heaviest pitch gear teeth (steel
hardened) of any rotator in its size and price range.
The HD-73 control unit features TWO-SPEED rotation with one
five-position switch. This presents a
one revolution per minute speed for rotating over an
extended arc and a slower speed for adjustment
of, say, several degrees one way or the other for fine
adjustments for the best signal on receiving and
The rotator not only has a readily accessible externally
located fuse for total unit protection, it also
has an internally mounted automatic reset thermal protector
for the motor and transformer against shorts
or possible connection error or prolonged operation.
A large, back-illuminated 3V2" Weston D’Arsonval, Taut Band,
linear, full scale, 90° swing meter is
calibrated in bold S-W-N-E-S as well as a degree-graduated
I he meter direction indicating voltage supply is solid
state voltage regulated for meter indication accuracy
regardless of wide line voltage or load variation; the
regulating range is 105 to 129 volts.
The HD-73 rotor was designed to operate antennas with a
maximum of 10.7 square feet of wind load
area when properly installed.