Abstract: The device according to the invention is intended for controlling the electrical continuity of the equipotential branchings of multi-layer printed circuits. It comprises selectors of a model of printed circuit to be controlled in order to effect, by superposition with the latter, the selection from the assembly E of the conductor elements accessible on at least one of the outer faces of the circuit, of two distinct sub-assemblies Ei and Ec, such that E=Ei+Ec; means for scanning said selectors in order to effect, by displacements in contact with the latter, detection of the defects in continuity; and indicators for translating the state of the electrical continuity in the branchings.

Abstract: For the purpose of testing units which contain electrical circuits, an interpretation circuit and a load circuit are connected to the output of the unit being tested by way of a line. A load circuit is provided which contains two constant current sources which are respectively variable in terms of current value and which are respectively connectible and disconnectible. The one constant current source therefore serves as a load current source and the three serves as a load current sink. A determination can be made, with the assistance of a variable control voltage, as to whether the load circuit operates as a current source or a current sink. The constant current source and the variable control voltage are connected to one another and to the line to the unit being tested by way of a diode bridge. A comparator circuit is connected to the same line and comprises an impedance and voltage level converter and two comparators. Separately variable reference voltages are supplied to the comparators.

Abstract: An electronic demand register divides a demand interval into a contiguous set of N demand subintervals. The demand in each demand subinterval is summed with the demands from the N-1 most recent contiguous demand subintervals to derive the interval demand. The interval demand is compared with a prior stored maximum demand to decide whether to discard the present interval demand or to use it to replace the previously recorded maximum demand. Demand is accumulated in terms of actual power usage by scaling power usage pulses according to the relationship in the particular meter on which the rolling demand register is used. Thresholds are provided for producing warning signals to alert the consumer to an actual or impending demand condition which may adversely affect billing.

Abstract: A circuit for detecting the failure of a step motor to respond to energization commands, which takes advantage of the time constant decrease of an energized phase which occurs due to stalling of the motor. A predetermined current level I in the energized phase is reached in a time interval TI which is shorter than a time interval TO necessary to reach the same current level when there is a response of the motor. The circuit comprises a timer having a predetermined period between TI and TO which activates a bistable circuit indicative of a failure to respond if the current level I is reached in a time shorter than the required time period.

Abstract: Measuring apparatus is presented which permits monitoring of current consumption of electronic equipment under operating conditions. The apparatus includes a probe-like element shaped to fit into the equipment fuse holder in place of the cartridge fuse and the cap which holds the fuse in place. A pair of test leads serve to encircuit the contacts within the fuse holder with the terminals of an ammeter. Subsequent to the completion of the monitoring act the probe-like element can be removed and the fuse and cap combination reinserted in the equipment.

Abstract: A passive voltmeter that measures pulses of high voltage by periodically charging a condensor through a spark gap. The frequency at which the spark gap breaks down is a function of the voltage being measured and is detected and displayed in volts. Radioactive material within the chamber is used to insure a constant breakdown voltage by supplying the necessary free electrons. This insures constant breakdown time for the arc with minimum jitter.