Difference between revisions of "S-4"

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* [http://w140.com/tek_S4_1985.pdf Tektronix S-4 Manual, revised 1985 (PDF)]
 
* [http://w140.com/tek_S4_1985.pdf Tektronix S-4 Manual, revised 1985 (PDF)]
 
* [http://w140.com/frye_s4_gate.pdf George Frye's Explanation of S-4 sampler in October 1968 Service Scope (PDF)]
 
* [http://w140.com/frye_s4_gate.pdf George Frye's Explanation of S-4 sampler in October 1968 Service Scope (PDF)]
* [[Media:Tek s-4 fcp april 1969.pdf|Tektronix S-4 Factory Calibration Procedure, April 1969 (PDF, needs OCR)]]
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* [[Media:Tek s-4 fcp april 1969 - OCR.pdf|Tektronix S-4 Factory Calibration Procedure, April 1969 (PDF, OCR)]]
 
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The '''Tektronix S-4''' is a sampling head for 7000- and 3S-series samplers.
 
The '''Tektronix S-4''' is a sampling head for 7000- and 3S-series samplers.

Revision as of 08:17, 10 September 2020

Manuals – Specifications – Links – Pictures

The Tektronix S-4 is a sampling head for 7000- and 3S-series samplers. It was designed by George Frye and introduced in 1968. It is the fastest of the S-series plug-in samplers.

Specifications

Rise time 25 ps (observed with S-50 or S-52, 35 ps)
Bandwidth 14.5 GHz
Input impedance 50 Ω (terminated SMA connector)
Input range 1 Vp-p (operating)
Maximum input ±5 V max. non-destructive
Noise < 5 mV
Features
  • trigger signal pick-off for internal triggering

Internals

The S-4 sampling gate is based upon a traveling wave trapped-charge transmission line in which the sampling window is set by the propagation time of a pulse edge through a thick-film transmission line. This technique requires only a sharp pulse edge rather than a precise pulse width, which is harder to generate. The sampling diodes are housed in a special coaxial connector that provides a high bandwidth signal path.

To disassemble the sampler hybrid, first remove it from the sampler board as per the manual. Remove the input connector using a 7/32" wrench and remove the 20 dB attenuator with small pliers. The ceramic board is held to the housing using roll pins that can be pressed out with a 0.030" pin punch. The hybrid has six diodes, each about 0.75mm square. The cathodes are glued to the gold substrate with conductive epoxy and the anodes are wire-bonded (twice) over a gap to the next step in the strobe line. It appears that a standard beam-lead diode may fit across the gap but cleanly removing a failed diode without damaging the substrate would be quite difficult.

Links


Pictures