01-31-2019, 03:09 PM
An extract from Controlling Suspended Sediment Samplers by Programmable Calculator and Interface Circuitry, USDA Forest Service, Research Note PSW-376, OCT 1985 (8 p.).
A programmable calculator connected to an interface circuit can control automatic samplers and record streamflow data. The circuit converts a voltage representing water stage to a digital signal. The sampling program logs streamflow data when there is a predefined deviation from a linear trend in the water elevation. The calculator estimates suspended sediment discharge from rating coefficients for the gauging site. When a threshold value of accumulated suspended sediment discharge is reached, the calculator sends a signal to the interface circuit that activates a pumping sampler. The sampling program is easily updated, and data are transferred to a computer by using a digital cassette recorder. This system increases sampling flexibility and efficiency.
BEST!
SlideRule
A programmable calculator connected to an interface circuit can control automatic samplers and record streamflow data. The circuit converts a voltage representing water stage to a digital signal. The sampling program logs streamflow data when there is a predefined deviation from a linear trend in the water elevation. The calculator estimates suspended sediment discharge from rating coefficients for the gauging site. When a threshold value of accumulated suspended sediment discharge is reached, the calculator sends a signal to the interface circuit that activates a pumping sampler. The sampling program is easily updated, and data are transferred to a computer by using a digital cassette recorder. This system increases sampling flexibility and efficiency.
BEST!
SlideRule