A two microfarad capacitor C-46, is placed across the discharging relay K-1 delaying actuation until the switching relay has transferred the step charging capacitors, Since the maximum pulse train duration is 3/4 of a second, 1/4 of a second is allowed for switching and discharging of the capacitor. To buck out the voltage developed across the step charger capacitors by the initial five pulses required for actuating the awitching circuit, the capacitors are discharged to a small negative bias. The negative bias supply providing this voltage is also used to bias the diode(V-5C), which serves as a discharge path for coupling capacitor C-53. The output bridge (V-1l and V-12) is a D.C. vacuum tube voltmeter capable of driving from 1 to 10 strip chart recorders should duplicate copies of the survey be desired. The recorder line card is plugged into J- so that the chart drive will run only when the read circuit is actuated. An oscilloscope 1s mounted on the fron* panel, displaying a portion of the input pulse train. A gain control (R-3) permits adjustment of the signal to an operating level which will reliably trigger the first Schmitt circuit. Power Supply - The B plus supply is electronically regulated because of the wide variations in current required by the Schmitt triggers. All critical stages are decoupled to eliminate spurious counts. 4.3 Operation The operational controls for the Telepulse Receiving Station are the bridge zero adjustment, the read and release push button switches, -~ yh -