6 1/2” O.D., 2 3/4” Deep. Solid brass case, polished and lacquered or chrome-plated (optional, extra). Dials 4 3/4” O.D., spun aluminum with black numerals or matte black with white numerals. Full 250° scale length, pivot and jewel movements, 300 micro amps full scale, 450 Ohms resistance with 180°/sec. response rate. Wind speed Gust Register response rate 75% Vv/5 seconds. Reset knob clutch torque less than 1 ft. lb., spring loaded.
Hand Held Anemometers
Cup shaft is stainless steel revolving between stainless ball bearings. Folding cups are made of Lexan. Instrument housing is black ABS material with 1/8” thick wall. Swept diameter on cups 5 3/4”.
Cup-type: 7 1/2” swept diameter, weighs 4 oz. It generates a sine wave AC voltage proportional to windspeed. At 102 MPH it spins at 1800 RPM, putting out 3.67 volts at 60Hz. Output linearly proportional down to 8 MPH. Black Lexan housing and rotor are impervious to shock, vibration, sunlight and ice. All generators are calibrated to a master to be interchangeable. Thrust and journal bearings are both O-ring mounted, self-aligning to Beryllium copper shaft, impervious to moisture and salt air. Bearings are self-lubricating Rulon J for dimensional stability under extreme conditions.
Wind Vane swept diameter 7 1/2” ”. Housing and bearings same as generator (above). Five solid brass 4-40 stud terminals for antenna rotor type cable. Permanent magnet actuates 8 hermetically sealed magnetic reed switches for long life. Diode logic system permits five wire operations.
Air and Water Sensors
Air: 3” overall height; 2” housing diameter. Probe is nickel-plated brass, 1/2” O.D., 1” long. Sensor element is a precision thermistor, a solid state device which changes its resistance inversely proportional with temperature from 150,000 Ohms at low end to 1,500 Ohms at high end. Interchangeability of thermistors is ± 0.2°C; time constant 10 sec.
Water: Thermistor specifications identical to Air Sensor. Housing is solid bronze rod, bored to accept thermistor in its very end and potted wiring. 3” long, 3/8” O.D. Water sensor is intended for boats. For pools, hot tubs, or any other application, consult Maximum.
Instruments requiring power are supplied with outlet-mounted transformers for 120-Volt AC household current. Where power is not available, most instruments are available to run off optional 12VDC power source. European voltages are available as an option.