- Email: [email protected]
LN2 cooled noise source
LN, cooled
noise
source
Liquid nitrogen cooled noise sources which provide an accurately known input noise temperature at certain calibration frequencies and a low vs w r over a full frequency range are manufactured by the Maury Microwave Corp. Several different models are available for use with different waveguides and any model can be modified
to cover different frequency ranges and broader bandwidths. Shown in the illustration above is Model SX8039A which is designed to cover a frequency range of IO.0 to 12.4 GHz with a 1.10 max vswr in a WR90 waveguide. All models are extremely compact, rugged, and are suitable for use in either field or laboratory. Precision index holes on the input flange ensure proper flange alignment and reliable repeatability. The operating temperature of all models is 77.36 K but the operating time varies since it depends on the dewar capacity which is different for different models. All models operate from an a c power supply of 115 V, 60 cycles, and require an external helium gas pressurization of 2 lb/i+. The calibration accuracy is in all cases t 1.0 K. Liquid nitrogen cooled sources have a variety of applications in cases where accurate noise temperature measurements are essential, such as radiometric type measurements, antenna system calibration, and parametric amplifier performance evaluation. [Maury Micro-
wave Corp., USA]
10373 Mills Ave., Montclair,
Conductivity
level
Calif. 91763,
controller
The NCB7 is a level controller designed by Fielden Electronics Ltd for electrically conductive liquids. By suitable choice of an electrode it can be adapted to fit a variety of applications, including measuring liquid oxygen and nitrogen levels. The system consists of an electrode, control unit with set pointer and scale in arbitrary units, and a power supply/control relay unit. Level controllers in conductive liquids normally rely on the large resistance increase which occurs when the electrode is uncovered and which can readily be measured and used to operate a control circuit. But in cases where the conductive liquid adheres to the electrode, providing a low resistance path from electrode tip to each, the circuit resistance when the electrode is uncovered only increases slightly. The NCB7 has been designed to detect these small changes. The controller has a resistance range of O-900 Q minimum and a differential of 4 R at 70% of scale. It is finding fairly extensive use in the food industry for level control and liquid presence control. [Fielden Electronics Ltd, Paston Road, Manchester M22 4TX, UK]
LH2 equipment
for
NASA
Cryogenic Consultants Inc. have been awarded a contract to design and engineer liquid hydrogen test equipment for the NASA Langley Research Center in Hampton, Virginia. This equipment will be used for static and dynamic research testing of hypersonic vehicles. For static testing, carried in a test cell, supplies of both liquid hydrogen and slush hydrogen will be required. A large scale slush hydrogen generator will be specially designed for this. Dynamic testing will be carried out in NASA’s 8 ft, high temperature structures tunnel. A preprogrammed pressure set point will be maintained in the tunnel by a hydrogen pressure control system to within 2%. Additional equipment provided will include an LH2 tank, high pressure LH2 bottles, high pressure gerseous hydrogen and helium bottles, high and low pressure LH2 transfer lines, electric power conductors, regulators, and a control centre. [Cryogenic Consultants Inc., 832 Hamilton St, Allertown, Pa 18101, USA]
Conferences Thermal
expansion
of solids
The second symposium on the Thermal Expansion of Solids will be held in Santa Fe, New Mexico, USA on 10-12 June 1970 under the joint sponsorship of the University of Illinois, Urbana, and the Sandia Laboratories. Papers are solicited on recent advances in theoretical and experimental studies of thermal expansion and its CRYOGENICS
. FEBRUARY
1970
relation to other properties of solids. Abstracts should be submitted to Prof. R. 0. Simmons Physics Department University of Illinois Urbana, Illinois 61803 by 30 March 1970. The proceedings will be published shortly after the conference. 79
noise
source
Liquid nitrogen cooled noise sources which provide an accurately known input noise temperature at certain calibration frequencies and a low vs w r over a full frequency range are manufactured by the Maury Microwave Corp. Several different models are available for use with different waveguides and any model can be modified
to cover different frequency ranges and broader bandwidths. Shown in the illustration above is Model SX8039A which is designed to cover a frequency range of IO.0 to 12.4 GHz with a 1.10 max vswr in a WR90 waveguide. All models are extremely compact, rugged, and are suitable for use in either field or laboratory. Precision index holes on the input flange ensure proper flange alignment and reliable repeatability. The operating temperature of all models is 77.36 K but the operating time varies since it depends on the dewar capacity which is different for different models. All models operate from an a c power supply of 115 V, 60 cycles, and require an external helium gas pressurization of 2 lb/i+. The calibration accuracy is in all cases t 1.0 K. Liquid nitrogen cooled sources have a variety of applications in cases where accurate noise temperature measurements are essential, such as radiometric type measurements, antenna system calibration, and parametric amplifier performance evaluation. [Maury Micro-
wave Corp., USA]
10373 Mills Ave., Montclair,
Conductivity
level
Calif. 91763,
controller
The NCB7 is a level controller designed by Fielden Electronics Ltd for electrically conductive liquids. By suitable choice of an electrode it can be adapted to fit a variety of applications, including measuring liquid oxygen and nitrogen levels. The system consists of an electrode, control unit with set pointer and scale in arbitrary units, and a power supply/control relay unit. Level controllers in conductive liquids normally rely on the large resistance increase which occurs when the electrode is uncovered and which can readily be measured and used to operate a control circuit. But in cases where the conductive liquid adheres to the electrode, providing a low resistance path from electrode tip to each, the circuit resistance when the electrode is uncovered only increases slightly. The NCB7 has been designed to detect these small changes. The controller has a resistance range of O-900 Q minimum and a differential of 4 R at 70% of scale. It is finding fairly extensive use in the food industry for level control and liquid presence control. [Fielden Electronics Ltd, Paston Road, Manchester M22 4TX, UK]
LH2 equipment
for
NASA
Cryogenic Consultants Inc. have been awarded a contract to design and engineer liquid hydrogen test equipment for the NASA Langley Research Center in Hampton, Virginia. This equipment will be used for static and dynamic research testing of hypersonic vehicles. For static testing, carried in a test cell, supplies of both liquid hydrogen and slush hydrogen will be required. A large scale slush hydrogen generator will be specially designed for this. Dynamic testing will be carried out in NASA’s 8 ft, high temperature structures tunnel. A preprogrammed pressure set point will be maintained in the tunnel by a hydrogen pressure control system to within 2%. Additional equipment provided will include an LH2 tank, high pressure LH2 bottles, high pressure gerseous hydrogen and helium bottles, high and low pressure LH2 transfer lines, electric power conductors, regulators, and a control centre. [Cryogenic Consultants Inc., 832 Hamilton St, Allertown, Pa 18101, USA]
Conferences Thermal
expansion
of solids
The second symposium on the Thermal Expansion of Solids will be held in Santa Fe, New Mexico, USA on 10-12 June 1970 under the joint sponsorship of the University of Illinois, Urbana, and the Sandia Laboratories. Papers are solicited on recent advances in theoretical and experimental studies of thermal expansion and its CRYOGENICS
. FEBRUARY
1970
relation to other properties of solids. Abstracts should be submitted to Prof. R. 0. Simmons Physics Department University of Illinois Urbana, Illinois 61803 by 30 March 1970. The proceedings will be published shortly after the conference. 79