BIG BOY ROTATOR MODEL PST-71D

FOR EXTREMELY HEAVY DUTY LARGE HF ANTENNAS AND ROTATING TOWER

The BIG BOY model PST-71D is rated AT 8.8 square meters of antenna load and is utilized in amateur, commercial, industrial and government applications.

The PST-71D was designed for heavy log periodic antennas (used in embassies around the world), 40/80 meter long booms, stacked arrays and rotating towers where winds and weather are a factor. To understand more, see the Real Truth tab.

Details

• High strength cast aluminium gear box
• Rugged and proven design
• Nickel chromium-molybdenum steel and bronze alloy gears running on ball bearings
• No maintenance, life lubricated
• Strength steel galvanized mast clamp
• Temperature range -40° to + 90°C
• Stainless steel bolts

Features of the PST-71D Rotator

• Rated at 8.8 square meters
• Rotating torque far superior to all other rotators manufactured by a factor of 2 to 3 (see Comparison Table Tab)
• Braking torque specifications exceed all rotator manufacturers by a factor of 2 (see Comparison Table Tab)
• Exceptionally high starting torque - specifications exceed all other rotators used in amateur/commercial radio applications today (see Comparison Table Tab)
• High power 24 Vdc motor
• Advanced DOUBLE worm gear technology, irreversible under mast torque
• Large chromolly steel output shaft 38 mm
• Time of rotation (approx.) - 2 minutes or more (programmable speed)
• Range of rotation - 500 degrees (360 +/- 70 degrees) (programmable)
• 52 mm to 75 mm compression jaws type mast clamp (included)
• Utilizes 5 conductor rotator cable
• Long cable runs (up to 180 meters)
• Rugged proven design (used for 10 years throughout Europe, Asia and the Far East)
• 2 year warranty - parts and labour

The following items are included in the package:

Rotor with mast clamp, stainless steel bolts, control box with power cord, rotor cable's connectors, printed user manual + CD with rotor tool software + extra instructions for RS232 users.

Please refer to the separate tab heading "Control Box D" for details

Control Box "D"

This control box gives you a fully computer programmable/controllable antenna rotator. You can configure it according to your specific antenna system requirements. It can become a controller for azimuth or elevation rotator.

During controller alignment and quality tests, the contoller has a default configuration, which can be reprogrammed using the "tool software" series supplied.

Users who do not have a PC, can change some controller feautures using on board dip switches.

Features of the new "D" Control Unit - A Fully Computer Controllable Controller

• Large digital display
• One degree read out accuracy
• Programmable speed
• Toggle switch for left and right
• Presets
• Solid state CPU controlled control unit
• RS232 built in
• Programmable auto reverse delay
• CE approved (European electrical code approval)

Features

South or North Stop (default = south stop, selectable by on board dip-switch or PC)

Soft Start - Soft Stop (10 degree starting-stopping soft ramp is provided. On - Off, selectable by on board dip-switch or via PC)

Rotation range (360° or 500° selectable travel limits by on board dip-switch, programmable by PC, between 1° and 500° with 1° steps)

Calibration and off-set. (Manual calibration and off-set is provided, both are even executable by PC)

Features programmable via RS232 only:

Reverse delay (do not allow the immediate antenna reverse rotation, default = 3 second, programmable)

Preset delay (delay time after a preset input command, default = 3 seconds, programmable)

PWM on-off (allow soft start-stop ramp, programmable)

PWM duty cycle (allow to control starting-stopping ramp and motor speed, programmable)

Optimizer (if extra range travel is selected, the rotor will start following the shortest way, programmable)

Rotor check (verify if the rotor feed back signals are as they have to be, if not it will stop the rotor within 5 seconds, programmable)

The front panel and manual commands:

The front panel contains: Power switch, CW and CCW toggle switches, Preset knob and display.

The "preset" is made by a rotative absolute encoder, which allows you to choose an antenna direction in the 0-360 degree range by rotating a knob.

When turning the preset knob, the display will show the wanted heading.

When you want to stop to rotate preset's knob, after a short delay time the rotor will start and will stop when it reaches the new chosen heading, while the display will show the antenna motion step by step .

The delay time is provided to allow you to change your mind before the rotator starts, and then you can input a new heading.

While the rotor is running after an input preset command or via RS232, you can stop it just by pushing momentarily one toggle switch.

General Specifications:

Control boxes are manufactured with the highest-quality components. The circuit is powered via an AC filter and a large transformer that provides the operating voltages for the controller and rotator motor. Two 10A long-life relays energize the rotor motor.

Another feature of the control box circuitry is the special way in which rotation limits are implemented. No limit switches are used in the rotators, but the limits are controlled electronically from within the control box.

This permits travel much greater than 360 degrees. Each Controller has 70° extra range on the left and right side, for 500° total. If the antenna is in 70° extra range, the display will show it.

The digital display shows the antenna bearing in degrees, true to 1 degree, as the rotor shaft has no play or backlash.

Control boxes and rotators are individually calibrated and checked before shipping.

User's manual:

The manual consists of three parts, one printed copy. Two parts are available as .PDF documents on CD, enclosed with rotator, for users who want to use RS232 and a computer.

The CD also contains the "tool software" which allows experienced software developers to write their own rotator control software.

Download Manual

• Big Boy PST User Manual

THE TRUTH ABOUT ROTATOR SPECIFICATIONS AND WHY THE PROSISTEL BIG BOY LINE IS DOING SO WELL

There are many factors that affect the ability of a rotator to turn or hold (brake) an antenna or array, in the short term as well as over the anticipated life expectancy of the rotator itself. These factors are both internal and external. Internal considerations are related to the design and construction of the rotator, including the housing, type of gear, type and size of motor and brake mechanism and associated control system, and the bearings, especially those that take the vertical and the lateral loads imparted by the antenna mast. External factors are related to the size and configuration of the antenna system to be rotated, whether or not the rotator is mounted inside of the tower with an external thrust bearing, the wind load (commonly expressed in square feet [sq. ft.] of effective surface area) along the mast, and the weight of the rotating system.

Most manufacturers simply state that their rotator will handle an antenna of a certain number of square feet. This is where magic and guesswork take over from physics and engineering. Knowing the surface area (sq. ft.) is not enough. Assuming that the wind load measurement is accurate, you would need to know the wind speed at which the rating has been established. Is it 50 mph or 80 mph, steady state or gusts, from which (or changing) direction? Does it make a difference if the elements or boom are long and thin or short and thick? Does it matter if the antenna is six inches or ten feet above the rotator or thrust bearing? Does it matter if there is one antenna on a five-foot mast or three antennas on a twenty-foot mast? Does it make a difference if it is below freezing and there is an inch of ice coating the whole business? You bet it does! In fact you may be betting your life or at least the life of your rotator on it.

How can you decide which rotator you need for your application? Let Prosistel take the guesswork out of it for you. It all pretty much boils down to a few not so mysterious specifications, and they relate to the torque or turning force available to get the system moving from rest, keep it turning, bring it to a stop and hold it in place. These specifications are called:

STARTING TORQUE - maximum turning force that the rotator is able to produce as it comes up to speed from a dead stop. The greater the starting torque and rotating torque the less time it takes for large arrays and stacks to come up to full rotational speed.

ROTATING TORQUE - turning force available to overcome friction and the effects of wind.

BRAKING TORQUE - amount of torque the rotator can resist that is induced by winds or other loads trying to rotate the antenna system from it's braked position.

VERY SIMPLY - The larger the numbers, the more the rotator can handle and the longer it will last.

Now, compare the starting, rotating and braking torque specifications of "BIG BOY" to any other rotator on the comparison table tab and you will be amazed. Also, take a good look at the weight differences, brake types, size of motors used and you be the judge. See for yourself how the BIG BOY line of rotators makes the others look like plastic toys.

See Comparison Table tab.