This section contains descriptions of circuit boards made for use with the Keck ADC project. It corresponds to the Boards tab in the schematics binder.
ADC Limit Sensor boards, EL-3605
Schematic: (None - PCB only)
Page last updated: October 3, 2006
The Limit Sensor boards are a set of four boards to which Cherry Hall-effect vane sensors are mounted. Each board provides five solder pads for a short ribbon cable to be attached to. The boards themselves can not have connectors soldered onto them because there would be clearance problems with the stage limit vanes. The boards are configured as follows:
On each board, Pin 1 supplies the V_LIMIT level and Pin 2 is GND. On board A, the AFT_2RET output is wired to Pin 3. On board B, the FWD_1RET output is wired to Pin 4 and the FWD_2RET output is wired to Pin 5. On board C, the AFT_HOME output is wired to Pin 3 and the AFT_2DPL output is wired to Pin 5. And finally, on board D, the FWD_HOME output is wired to Pin 3, the FWD_1DPL output is wired to Pin 4, and the FWD_2DPL output is wired to Pin 5.
Due to space limitations, the Cherry sensors have each been modified by cutting off one mounting tab. Because of this, each sensor is held down by only one screw. To maintain alignment, a small dab of epoxy has been placed on each side of the sensor body on the opposite side as the hold down screw. NOTE: the spares complement for the ADC contains a spare of each sensor board plus 3 spare, modified sensors.