DC502

Manuals – Specifications – Links – Pictures

The Tektronix DC502 is a 550 MHz frequency counter plug-in for the TM500 system.

It measures frequencies from 10 Hz to 550 MHz or totalizes events up to the readout capacity of 10⁷−1 at the maximum rate of 550 MHz.

Key Specifications

Resolution	7 digits
Frequency range	10 Hz to 110 MHz (Direct input); 50 MHz to 550 MHz (÷10 input)
Sensitivity	300 mVp-p or 100 mVrms sine (Direct input); 500 mVp-p or 170 mVrms sine (÷10 input)
Input impedance	1 MΩ (Direct input); 50 Ω (÷10 input)
Gate time	0.01 s, 0.1 s, 1.0 s, or 10 s
Stability	1×10−5 (10 ppm) standard, 5×10−7 (0.5 ppm) with Opt.01
Features	7-digit LED Display, automatic decimal point and leading zero blanking manual Start/Stop (Totalize) adjustable trigger level on direct input
Options	Opt.05 – TCXO Opt.07 – to display SW503 marker (Tekscope V.8 N.1 p.20 and 070-2051-00 p. 5-3 – more information needed)

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.

LEDs indicate when the gate is armed, and whether displayed numbers are in kHz or MHz, and when register overflow occurs.

The internal clock is 1 MHz. The Opt.05 high stability oscillator runs at 5 MHz with an additional by-5 divider.

Links

• DC502 @ barrytech.com

Rear Interface

Connector Pin	Signal
28B	Second decimal point output
27B	MHz light output
27A	Internal Scan Clock Disable
26A	/RESET
25B	External Scan Clock input
25A	Time Slot Zero
24B	Internal Scan Clock output (2 kHz)
23B	Overflow
22B	MSD output
21B	BCD output 2
20B	BCD output 8
20A	BCD output 4
19A	BCD output 1
19B	Data Good

Data is output serially by digit.

Pictures

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  DC502 in TM515 with other TM500 gear