S-6, 36 C, 14th Commercial Street,
Phase II ext., D.H.A.,
Karachi, Sind 75500
ph: 923332111544
fax: 92215382658
alt: 92215312477, 92215318378
info
Meteorological Instruments
We offer a wide variety of Meteorological Instrumentation starting from such simple equipment as Sunshine Recorders to such more complicated SODAR Wind Profilers etc. The Equipment are backed by after sales Services and continous support through our Principals. Our Instruments are manufactured by world renowned Meterological Instrumentation Companies.
SODAR WIND PROFILER WITH RASS FROM REMTECH
SODAR SYSTEM OVERVIEW
Our phased array Doppler Sodars continuously and reliably measure wind speed and direction, vertical motions, turbulence, thermal structure, and mixing depth at heights ranging from 15 m up to 1,000 to 5,000 meters depending on the type of antenna. Briefly, this measurement is accomplished by emitting a strong acoustic pulse in the audio band and detecting the Doppler frequency shift of the received backscattered echo. This backscattered echo signal is due to thermal turbulence in the atmosphere. The signal frequency shift (Doppler shift) and its relative strength are processed in various ways to produce far more information than previously available through conventional methods such as instrumented towers, tethersondes, etc.
All three dimensional REMTECH monostatic Doppler Sodar systems basically consist of one sole antenna (phased array type) and an electronic case. In the electronic case are the computer, transceiver, and power amplifier. Also included are interconnecting cables and a small mount for the antenna.The system allows for full control of the antenna beams: four of the electronically steered beams are tilted (30° or 15°) or from vertical and turned 90° from each other to provide the horizontal component of wind velocity. The last beam is pointed vertically and provides that component of the wind. The system software controls the sequence and rate of operation for each beam. These are non system parameters which can be changed through keyboard input. Different antennas are available for different ranges.
A major advantage of the REMTECH Doppler Sodar Systems is their tremendous user flexibility. Virtually all important parameters, such as averaging and sampling times, transmitting power, antenna orientation, range gates, and maximum range, are operator selectable by simple key-in options to the minicomputer.The exclusive signal to noise detection and comparison techniques developed by REMTECH through several years of research, permit the system to produce reliable data in a noisy environment with comparatively short data averaging times because of the discrete rejection of all spurious signals. Data which are, in fact, considered suspect, due to adverse ambient-noise, are deleted from the system. This prevents users from being misled by erroneous data. No additional data processing is required in order to achieve the system's full accuracy. Data archived can also be directly processed to provide complete statistical data summaries and climatological analyses.System maintenance is greatly facilitated by special software diagnostic routines. If ever required, repair is accomplished by swapping the complete electronic case, vastly reducing down time.
Campbell Stokes Sunshine Recorder
The picture shows a Campbell Stokes Sunshine Recorder (Universal Mk3A), one of a batch of 16 made in our Meldreth Workshops using CNC and conventional machine tools - For more information on our manufacturing facilities go to the 'Production Department' in the 'Products' - 'Conventional Instruments' section.
Technical Details
Adjustment for latitude:
MkIIIA Tropical - 0° to 40° N or S
MkIIIB Sub-Tropical - 25° to 45° N or S
MkIIIC Tropical - 45° to 65° N or S
Sphere: 102mm +/- 1.3mm diameter.
Focal length for sodium D light, 74.9mm
+/-0.25mm
Dimensions: 240 x 187 x 165mm
Weight: 4.3kg
General Description
This instrument is manufactured to a proven design and is of the type used extensively by meteorological services world wide. In 1964 this design was adopted by the World Meteorological Organisation as their Interim Reference Recorder for use in all member countries.
The sphere, made of well-annealed colourless optical glass is securely clamped on a semi-circular metal arc by means of two bosses attached precisely across a diameter and located by an adjusting screw onto the ball ended boss. Also mounted on the arc is a bowl of spherical section
machined from gunmetal. This bowl has the shape of a belt cut from a hollow sphere and contains three overlapping pairs of grooves in which record cards suitable for different seasons can be inserted and secured by a screw. The metal arc is mounted in a grooved slide to permit the inclination of the sphere and bowl to be adjusted for geographical latitude.
The slide is mounted on a T-shaped metal base which is supported on levelling screws on a fixed metal sub-base.
Interpretation of Records
The record cards are made from a special board with a matt turquoise finish on which even weak sunlight produces a clearly visible trace. They are treated to char rather than burn so that the trace produced by strong sunlight does not spread significantly.
There are three types of card to correspond to the behaviour of the sun at different seasons: long curved for use in summer, straight for use near the equinoxes and short curved for use in winter.
All are marked with hourly intervals, and may be used in either the northern or the southern hemisphere.
Ordering Information:
FM4100 Campbell Stokes Sunshine Recorder (Universal MkIIIA) Tropical
FM4101 Campbell Stokes Sunshine Recorder (Universal MkIIIB) Sub-Tropical
FM4102 Campbell Stokes Sunshine Recorder (Universal MkIIIC) Temperate
FM4150 Campbell Stokes Sunshine Recorder (German Pattern)
FM4120 1 years supply of sunshine Cards
FM4121 100 Summer Cards
FM4122 100 Winter Cards
FM4123 100 Equinoctial Cards
FM4124 Transparent Template
FM4125 Sphere Centreing Gauge
FM4126 100 Summer Cards (German)
FM4127 100 Winter Cards (German)
FM4128 100 Equinoctial Cards (German)
FM4129 1 years supply of sunshine cards (German)
S-6, 36 C, 14th Commercial Street,
Phase II ext., D.H.A.,
Karachi, Sind 75500
ph: 923332111544
fax: 92215382658
alt: 92215312477, 92215318378
info
