Instrumentation laboratory is located at AMD Headquarter, Hyderabad and is engaged in designing, developing and fabricating the instruments required for exploration programme. A full-fledged workshop supports these activities. The instruments, which have been fabricated in this regard, are:
1. Airborne gamma ray spectrometric (AGRS) system : In the initial days of airborne survey, the system developed in-house was based on TTL logic IC’s. This system was used till 1987. In order to reduce the bulk of the instrumentation and thus the payload, a new CMOS logic IC based system was designed which supported the survey operation till 1996. With the arrival of microprocessor based technology, the system was again redesigned and integrated with a notebook PC with far more compactness so that it can be accommodated in a single rack along with additional three fiber box detector packages weighing about 500 kgs with 200 watts power consumption at 28 VDC. The heart of the instrumentation is a dedicated 8088 microprocessor based Data Acquisition System (DAS), which acquires every second MCA (256 channels for 4 pi and 64 channels for 2 pi) data and transmits it to a notebook PC hard disk through Centronics port. The system uses a set of NaI (Tl) detector for 4 pi (downward looking) and 2 pi (upward looking) geometry applications having 50,000 and 8,500 cc volume, respectively. The system has a sensitivity of 0.2% K, 1 ppm eU, and 2 ppm eTh.
2. G. M. Counter and Scintillometers: The hand held Geiger Muller Counter and Scintillometers which are used by field officers in survey work are designed and fabricated in-house. These instruments are currently being commercially produced and marketed by Electronic Corporation of India Limited (ECIL).
3. Portable 4-channel Gamma ray Spectrometer: It is compact, rugged, lightweight spectrometer and comprises of a 8085 microprocessor, standard peripherals and a scintillation detector of size 1.75” x 2”. It is used for insitu measurement of gross counts, and radioelement concentrations of uranium (U), thorium (Th), and potassium (K) with LCD alpha numeric display. The device is indigenously designed and fabricated.
4. Borehole logging system: Two types of logging systems have been designed and indigenously fabricated.
(a) Gross gamma measuring systems with GM and scintillation detectors to display ore grade in %eU3O8. The most widely used count rate meter (SBL-2A) is recently replaced by digital count rate meter (DCRM). The digital count rate meter weighing 550 grams and measuring 9cm x 20cm x 7cm operates at single battery of 9V. The main features of the system are LCD simulation of analog meter, computation of grade values with/ without casing corrections, self-calibration with secondary standard.
(b) Microprocessor-based gamma-ray spectral logging with scintillation detector to trace the analog profiles of total, K, U and Th channels with corresponding depth. This system is being tested in the field in different areas for its performance.
5. Core analysis system: It is microcontroller based Core Analysis System used for evaluating the grade of radioactive core samples in terms of eU3O8 with individual high-voltage biasing of the GM tubes, thus enhancing the efficiency of each GM tube. Counts acquired from each GM tube are digitally summed for reducing the Dead time and count losses. The unit can be operated, stand-alone or through a personal computer with software for computation of grade values.
6. Microprocessor based Bulk Ore Analyser : It contains 6 scintillation detectors to compute the grade of the ore in % eU3O8 carried in 25-ton dumper from mine. It was designed and fabricated for UCIL.
7. Other Instruments:
a) Portable audio-visual scintillometer. b) Carborne gamma survey system (microprocessor-based) for total, K, U and Th. c) Light weight mine face scanner with beta-sensitive Geiger Muller (GM) tubes.