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 It was introduced in 1972 at the launch of the TM500 system, and superseded by the DC503A in 1981.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

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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