Counter Plug-ins : Tektronix DC502

· Counts to 550 MHz with /10 Prescale (50 Ohm Input).

· Direct Counting to 110 MHz

· 7 Digit LED Display

· Manual Start/Stop (Totalize) The DC 502 Digital COunter measures frequencies from 10 Hz to 55 MHz or totalizes events up to the readout capacity of 10x7-1 at the max rate of 550 MHz. Frequency measurements are accomplished using on of two inputs. The DIRECT INPUT has a frequency range of 10 Hz to 110 MHz, a 1 megohm input impedance, 300 mV p-p sensitivity (100 mV rms sine wave) and an adjustable trigger level range. The /10 PRESCALE INPUT has a frequency range from 50 MHz to 550 MHz with a 500 mV p-p sensitivity (170 mV rms sine wave) and a 50 Ohm input impedance. The manual totalizing mode with front panel start stop control is available in both inputs; from the prescale input, 1 displayed count per 10 input events will result. Measurement display is accomplished with 7 segment LEDs in a seven digit readout. The decimal point is automatically positioned by the measurement interval seleted, and leading zeros ( those to the left of the most sig digit or those to the left of the decimal point) are blanked. LEDs indicate when the gate is armed, and whether displayed numbers are in kHz or MHz, and when register overflow occurs. Four gate times of 0.01 s, 1.0 s, and 10 S are provided. A standard internal 1 MHz clock is provided with 1x10-5 accuracy.