DC503

Manuals – Specifications – Links – Pictures

The Tektronix DC503 is a 100 MHz, 7-digit frequency counter plug-in for the TM500 system. . It was introduced in 1972 at the launch of the TM500 system, and superseded by the DC503A in 1981.

Opt.01 is an OCXO for improved stability.

Key Specifications

Resolution	7 digits
Frequency Range	0.1 Hz (AC coupled: 10 Hz) to 100 MHz
Impedance	1 MΩ paralleled by approx. 20 pF
Sensitivity	300 mVp-p sinewave times attenuation to 100 MHz
Max Input Voltage, 1× Att.	50 V @ ≤2 kHz, derate –20 dB/decade to 10 MHz; 10 V @ 10 kHz to 25 MHz, derate –20 dB/decade to 50 MHz; 5 V @ 50 MHz to 100 MHz
Max Input Voltage, 10×/100× Att.	500 V @ ≤2 MHz, derate –20 dB/decade to 100 MHz
	— Standard time base —
Frequency	1 MHz ± 1 × 10-7 at cal
Error	≤ ±1 × 10-5 from 0 °C to +50 °C
Aging	≤ ±1 × 10-5 per month
	— Opt.01 OCXO time base —
Frequency	5 MHz ± 5 × 10-9 at cal
Error	≤ ±5 × 10-7 from 0 °C to +50 °C (after oven warm-up)
Aging	≤ ±1 × 10-7 per month

Gerbers

• Divide-by-5 circuit board gerbers 670-3300-00 (ZIP)

Rear interface

	27A – Internal scan clock disable
	26A − Reset, in/out
25B − Ext scan clock in	25A − Time slot zero (TS0)
24B − Scan clock out
23B − Overflow disp.dis. in
22B − Overflow out
21B − BCD out 2	21A − TTL Clock Input
20B − BCD out 8	20A − BCD out 4
19B − Latch Out (Data Good)	19A − BCD out 1
17B – Ch B Input	17A – Ch A Input GND
16B – Ch B Input GND	16A − Ch A Input
	14A − 1 MHz clock out

Pictures

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  DC503 front (older version) in operation

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  DC503 front (older version)

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  DC503 front (newer version)

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  DC503 in operation

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  DC503 and PG502 in a TM503

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  DC503 rear

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  DC503 top

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