6.1 Electronic equipment
G.C. Harper, T.B. Kalka, A.W. Myers and T.D. Van Wechel
Along with the normal maintenance and repair of the Nuclear Physics Laboratory electronic equipment, projects undertaken by the electronics shop this year included the following:
a. Three light pulsers were manufactured to support the new three-spectrometer setup and beamline for high energy gamma ray experiments (see Section 6.7).
b. A VME interface has been developed for the STAR TPC high voltage regulation system (see Section 4.14).
c. The SNO neutral current detector preamp reported in last years report as a prototype has been fabricated on hybrid circuits and tested satisfactorily (see Section 2.2).
d. The preamplifier for emiT has been constructed in a hybrid circuit and tested satisfactorily. We are currently designing the layout of the mother board for these preamps. The mother board will be approximately 2.5" by 13.5" and will contain 16 detectors, preamps and associated circuitry (see Section 1.9).
e. We have assisted in the design, layout and component placement of a shaper/ADC board with a VME interface to be used in the emiT experiment (see Section 1.10). This board is an 8 layer, .062" thick, 6U VME board with both surface mount and through hole components.
f. We have manufactured prototypes of the following for SNO: log amps, MUX and a fast shaper (see Section 2.2).
g. We manufactured an RS232 interface for use with a Lecroy HV4032A High Voltage power supply.
h. We designed and built a circuit to be used with a Pirani vacuum sensor. This circuit consists of a meter, a meter zeroing pot, a setpoint pot, an LED to indicate if the circuit is set to adjust the set point, a toggle switch to change between setpoint and sensor reading, an LED to indicate GOOD vacuum and an LED to indicate POOR vacuum. This circuit has been incorporated into 2 separate 5 1/4" chassis with 4 circuits per chassis. Each circuit has a corresponding relay on the back of each chassis to connect an external monitoring system if desired.
This past year we have upgraded our electronics shop capabilities to include surface mount rework and manufacturing circuit boards utilizing surface mount components. We received an OK Industries Pick and Place machine from the Super Conducting Super Collider closeout equipment. We have added our own video system to this equipment to aid in the placement of SMT components. We have purchased an OK Industries SMT rework/reflow station.
Recently we utilized both of these systems to populate the boards mentioned in item e above. We are further upgrading our SMT capabilities. This coming year we will purchase a reflow batch oven. This will significantly reduce the time required to manufacture and or populate circuit boards.