Abstract: A method of measuring a level of a material in a tank. A first secondary reference (FSR) signal is generated when a reference pulse is transmitted into the tank and a second secondary reference signal (SSR) signal is generated when an echo signal responsive to the reference pulse is received. A plurality of FSR signals and a plurality of SSR signals are stored. The plurality of FSR signals and plurality of SSR signals are transferred to a correlator block which calculates a plurality of correlation function values (CFVs) that have magnitudes reflecting a degree of matching between pairs of the SSR signals with their associated FSR signals. Using a maximum CFV result a time interval (Tm) is calculated between the FSR signal and SSR signal associated with the maximum CFV result, and the level of material in the tank is determined from Tm.

Abstract: Functional diagnostic testing of an electronic circuit board assembly with one or more embedded channels to be tested includes steps of: (a) connecting a channel under test; (b) imposing a known digital or analog voltage, as appropriate for a channel under test, that is generated by a digital or analog output of the electronic circuit board assembly; and (c) comparing data read by the channel under test with the stored value of the imposed voltage and required tolerance to determine whether the channel under test is within specifications. Diagnostic test implemented by digital logic and software residing onboard the electronic circuit board assembly. Execution of software or firmware code segment controls the diagnostic test sequence. Signal switching is facilitated by digital and analog multiplexers.

Abstract: A method of measuring a level of a material in a tank. A first secondary reference (FSR) signal is generated when a reference pulse is transmitted into the tank and a second secondary reference signal (SSR) signal is generated when an echo signal responsive to the reference pulse is received. A plurality of FSR signals and a plurality of SSR signals are stored. The plurality of FSR signals and plurality of SSR signals are transferred to a correlator block which calculates a plurality of correlation function values (CFVs) that have magnitudes reflecting a degree of matching between pairs of the SSR signals with their associated FSR signals. Using a maximum CFV result a time interval (Tm) is calculated between the FSR signal and SSR signal associated with the maximum CFV result, and the level of material in the tank is determined from Tm.

Abstract: Functional diagnostic testing of an electronic circuit board assembly with one or more embedded channels to be tested includes steps of: (a) connecting a channel under test; (b) imposing a known digital or analog voltage, as appropriate for a channel under test, that is generated by a digital or analog output of the electronic circuit board assembly; and (c) comparing data read by the channel under test with the stored value of the imposed voltage and required tolerance to determine whether the channel under test is within specifications. Diagnostic test implemented by digital logic and software residing onboard the electronic circuit board assembly. Execution of software or firmware code segment controls the diagnostic test sequence. Signal switching is facilitated by digital and analog multiplexers.