Tektronix DC503A Universal Counter/Timer

The DC 503A Universal Counter/Timer is designed to operate in a TM 500-series power module.

The instrument has two input channels, CH A and CH B, each with 125 MHz capability. Each channel has separate triggering level, triggering slope, attenuator, and coupling mode controls.

The DC 503A has eight measurement functions: FREQUENCY A, PERIOD B, WIDTH B, TIME A-B, RATIO A/B, EVENTS A DURING B, TOTALIZE A, and TIME MANUAL. All of the modes except FREQUENCY A, TOTALIZE A, and TIME MANUAL have the capability of averaging the selected measurement over a range of 1 to 10(exp 8) times the input signal. The signals to be counted or measured can be applied via front panel bnc connectors or throught the rear interface.

The triggering level for each channel can be monitored via the front panel or the rear interface connections. The buffered voltage available at these connectors corresponds to the trigger levels set by the front panel controls.

The output of the internal signal shaping ciruits can also be monitored via front panel connectors. These shaped signal outputs are useful in setting the triggering points on complex waveforms.

Measurement results are displayed in an eight digit LED readout. The decimal point is automatically positioned and leading zeros are blanked. Single annunciators (LEDs) are used to indicate register overflow, active gating interval, and the frequency or time units associated with the measurement being made.