Abstract: This specification discloses a timing control circuit for a strobe lamp used in adjusting the ignition timing of an internal combustion engine. The control circuit includes an ignition firing detector with improved noise immunity, and a calibrated control for setting a strobe flash for a predetermined deviation from ignition firing. The output signal of the calibrated control is coupled to a first amplifier to determine the slope of a ramp voltage in part determining the flash point of the strobe lamp with respect to ignition firing. The output of the first amplifier is coupled to a second amplifier which generates a ramp voltage at the predetermined slope above a diode forward breakover voltage at the input to the second amplifier. The voltage drop across the diode, prevents false triggering by noise with a magnitude less than the diode voltage even when the maximum amplitude of the ramp voltage is near zero.

Abstract: This specification discloses a connector adaptor for electrical interconnection with a diagnostic connector in an automobile. The connector adaptor permits easy access to and labeling of a diagnostic connector which can include, for example, an aligned row of recessed terminals. The connector adaptor includes a panel supporting a plurality of generally L-shaped conductive strips each having a terminal section and a generally perpendicular leg section. The leg sections are of different lengths so that the terminal sections can be spaced along the panel surface sufficiently far apart to permit easy access. Identification for each of the terminal sections can also be provided on the panel surface.