Abstract: An improved hand held starting/charging system tester. According to one aspect of the present invention, the portable handheld tester includes a connector to which various test cables can be removably connected to the tester. Detection circuitry within the tester determines which of several types of test cable is connected to the tester before testing. According to another aspect of the present invention, the portable handheld tester includes an improved user interface that permits a user to review test data from previously performed tests and further permits a user to either skip a previously performed test (thereby retaining the previously collected data for that test) or re-do the test (thereby collecting new data for that test). According to yet another aspect of the present invention, the portable handheld tester that performs a more complete set of tests of the starting/charging system.

Abstract: An electronic battery tester is disclosed with normal test and cold test modes comprising: a first circuit for applying an AC current load to a battery under test to induce an AC signal across the terminals of the battery; a second circuit for measuring the induced AC signal and converting it to a first voltage potential signal which is a measure of the battery's internal resistance; a circuit for adjusting the first voltage potential signal to a second voltage potential signal; third circuit for generating a threshold voltage potential signal at a first value when the battery tester is in a normal test mode and at a second value when the battery tester is in a cold test mode; and a comparison circuit for comparing said second voltage potential signal to said threshold voltage potential signal to determine a condition of the battery.

Abstract: A method of measuring a condition of a battery is disclosed comprising the steps of: inducing an AC signal across the terminals of the battery by applying an AC current load thereto; measuring the induced AC signal and converting it to a first voltage potential signal which is a measure of the battery's internal resistance; applying the first voltage potential signal across a voltage divider network calibrated in accordance with a predetermined battery rating scale to render a multiplicity of second voltage potential signals at a corresponding multiplicity of taps along the voltage divider network, values of the second voltage potential signals being representative of the calibrated battery rating scale; and sequentially selecting the second voltage potential signals along the taps for comparison with a threshold voltage potential signal to determine a measure of the condition of the battery.

Abstract: An electronic meter for testing engine parameters includes a slide switch and related circuitry for detecting, scaling and displaying the correct value of engine speed for both a conventional four stroke engine and a DIS four stroke engine, as well as for a two stroke engine. The electronic meter has a pickup which is adapted to be placed around a lead from a spark plug in the engine. The electronic meter is adapted to be triggered when a current spike in the spark plug lead is above a selected threshold value. When the electronic meter is triggered, a voltage pulse is stored in an integrating circuit in the meter. The electronic meter scales the voltage across the integrating circuit, measures the scaled voltage, and displays the value on the meter. The slide switch and associated circuitry for the electronic meter are adapted to vary the threshold level for the trigger, as well as appropirately reduce the output voltage of the integrating circuit, depending on the type of engine being tested.