S-52

Manuals – Specifications – Links – Pictures

The Tektronix S-52 is a pulse generator head compatible with S-series sampling units like the 3S2, 7S11, and 7S12. It was designed by Murlan Kaufman. It makes use of US Patent US3612910A, "Triggered Pulse Generator Having Automatic Bias Adjustment".

It puts out a 200 mV pulse into a load of 50 Ω. The pulse has a rise time of 25 ps or less. The output is an SMA connector.

In addition to the main pulse output, the S-52 also produces a pre-trigger pulse 85 ns before the main pulse. The delay is generated with a digital counter, and jitter between the pre-trigger pulse and the main pulse is specified as less than 10 ps. The pre-trigger pulse uses a BSM connector.

Key Specifications

Rise time	< 25 ps
Output amplitude	200 mV into 50 Ω (SMA)
Pulse Duration	> 350 ns
Output impedance	50 Ω «reverse terminated» (i.e. having controlled source impedance)
Pre-trigger output	85 ns before main pulse (jitter < 10 ps), +1 V into 50 Ω (BSM)

Internals

The S-52 generates the main output pulse using a 50 mA low-capacitance tunnel diode with part number 153-0040-00.

The S-52 is similar to the S-50, but the S-50 has twice the pulse amplitude. The reason for this is that the S-52 has a 48 Ω resistor between the output tunnel diode and the output connector providing back termination, while the S-50 has no such resistor. Although the S-52 produces a smaller pulse, its output impedance is much better controlled than that of the S-50, and the output resistor may also provide some limited protection for the output tunnel diode.

The S-52 uses a 156-0048-00 (LM3046) transistor array in the timing board.

Links

• Tek S-52 page @ amplifier.cd
• Tektronix S-52 @ barrytech.com

Documents Referencing S-52

Document	Class	Title	Authors	Year	Links
Rochester LLE Review Volume 25.pdf	Article	Computerized, Wide-Bandwidth, Multichannel, Soft X-Ray Diode Spectrometer for High Density Plasma Diagnosis		1985	7S12 • S-52 • S-6 • LM7912 • LM7912A • 7912DPO
RISOM2873.pdf	Article	Improvement of the Bandwidth of the Transient Digitizers in the LIDAR Thomson Scattering Diagnostic on JET	Erik Kristensen	1990	7912AD • 7A29 • 7704A • 7S12 • S-6 • S-52

Patents that may apply to S-52

Page	Title	Inventors	Filing date	Grant date	Links
Patent US 3612910A	Triggered pulse generator having automatic bias adjustment	Gene Cowan • George Frye	1970-07-28	1971-10-12	S-52

See Also

• 25ps Push-Pull Pulse Generator

Pictures

• 

  S-52 front

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  S-52 front A-prototype

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  S-52 pulse generator and S-6 sampling head in a 7S12 TDR/Sampler plugin

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  A-prototype of S-52

Internal

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  A1 Timing board (right)

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  A3 Trigger board (left)

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  A2 Tunnel Diode Control board (center)

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  Tunnel diode mount

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  Tunnel diode mount, detail

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  Schematic

Measurements

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  TDR "Self Portrait" — pulse reflected on S-6 "through" path (approx. 120 ps one way)

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  7S12 displaying the incident pulse from an S-52 (nom. < 25 ps) through an S-6 head (nom. < 30 ps). Displayed rise time ~35 ps confirms spec.

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  Full pulse pattern of a 7S12/S-52 in real time (top trace) and sampled (bottom trace) shown simultaneously on 7844. 7S12 trace at slowest possible sweep.

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  S-52 pulse in real time (top trace) and sampled (bottom trace) shown simultaneously on 7844. Approximately equal time scales.

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  Full pulse pattern of a S-52 (A-prototype) , driven by 3S6 (freerunning)