S-4: Difference between revisions

Revision as of 10:01, 13 March 2022

Tektronix S-4

Sampling Head

Compatible with 7000 and 3S series sampling heads

Produced from 1968 to 1990

Manuals

(All manuals in PDF format unless noted otherwise)

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.

Key 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 V_p-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.

Prices

1979: $1,435 (~$5,600 in 2022 Dollars)

According to an internal memo, in 1979 annual sales were estimated at 150 units.

Links

Pictures

Top view of the S4 plug-in
Left view
Right view
Schematic
Sampler board, strobe side
Sampler board, preamp side
Sampler board, disassembled with parts orientation
Microphotograph of sampler hybrid
S-4 B-prototype, no difference to standard S-4
S-4 in 7S11
S-4 in 7S11

@@ Line 1: / Line 1: @@
-{{Plugin Sidebar 2 |
+{{Plugin Sidebar
-title=Tektronix S-4 |
+|manufacturer=Tektronix
-summary=Sampling Head |
+|series=7000 and 3S series sampling heads
-image=Tek-s-4.jpg |
+|type=S-4
-caption=S-4 head |
+|summary=Sampling Head
-series={{3S+7S}} |
+|image=Tek-s-4.jpg
-introduced=1968 |
+|caption=S-4 head
-discontinued=1990 |
+|introduced=1968
-manuals=
+|discontinued=1990
+|designers=George Frye
+|manuals=
+* [[Media:070-0896-01.pdf|Tektronix S-4 Instruction Manual, Revised OCT 1986 (OCR, PDF)]]
 * [http://w140.com/tek_s4.pdf Tektronix S-4 Manual, copyright 1969 (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)]
+* [[Media:Tek s-4 fcp april 1969 - OCR.pdf|Tektronix S-4 Factory Calibration Procedure, April 1969 (PDF, OCR)]]
 }}
-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.
+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.
 {{BeginSpecs}}
@@ Line 18: / Line 24: @@
 {{Spec | Bandwidth | 14.5 GHz }}
 {{Spec | Input impedance | 50 Ω (terminated [[SMA connector]])}}
-{{Spec | Input range | operating, 1 V<sub>p-p</sub>; max. safe overload, ±5 V }}
+{{Spec | Input range | 1 V<sub>p-p</sub> (operating) }}
+{{Spec | Maximum input |  ±5 V max. non-destructive  }}
 {{Spec | Noise | < 5 mV}}
 {{Spec | Features |
@@ Line 26: / Line 33: @@
 ==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 [[Sampler#Six-Diode_Sampler|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
+To disassemble the sampler hybrid, first remove it from the sampler board as per the manual.
-connector using a 7/32" wrench and remove the 20 dB attenuator with small plyers.  The ceramic board is held
+Remove the input connector using a 7/32" wrench and remove the 20 dB attenuator with small pliers.
-to the housing using roll pins that can be pressed out with a 0.030" pin punch.  The hybrid has six diodes,
+The ceramic board is held to the housing using roll pins that can be pressed out with a 0.030" pin punch.
-each about 0.75mm square.  The cathodes are glued to the gold substrate with conductive epoxy and the anodes
+The hybrid has six diodes, each about 0.75mm square.
-are wire-bonded (twice) over a gap to the next step in the strobe line.  It appears that a standard beam-lead
+The cathodes are glued to the gold substrate with conductive epoxy and the anodes
-diode may fit across the gap but cleanly removing a failed diode without damaging the substrate would be
+are wire-bonded (twice) over a gap to the next step in the strobe line.
-quite difficult.
+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.
+==Prices==
+: $1,435 (~$5,600 in 2022 Dollars)
+According to an [[Media:Tek Schottky Diodes Memo rot.pdf|internal memo]], in 1979 annual sales were estimated at 150 units.
 ==Links==
 * [http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_7000_series_special/S4.html S-4 page @ amplifier.cd]
 * [https://kh6htv.files.wordpress.com/2015/11/an-02a-oscopes.pdf James R. Andrews, ''Comparison of Ultra-Fast Rise Sampling Oscilloscopes''. Picosecond Pulse Labs App Note AN-2a, 1989]
 ==Pictures==
@@ Line 46: / Line 60: @@
 Tek-s-4.jpg
 Tek s4.jpg
-S4_top.jpg|Top view of the S4 plug-in
+S4_top.jpg | Top view of the S4 plug-in
-S4_left.jpg|Left view
+S4_left.jpg | Left view
-S4_right.jpg|Right view
+S4_right.jpg  |Right view
-S4 schem.png|Schematic
+S4 schem.png | Schematic
-Tektronix-S4-sampler-board-strobe.jpg|Sampler board, strobe side
+Tektronix-S4-sampler-board-strobe.jpg | Sampler board, strobe side
-Tektronix-S4-sampler-board-preamp.jpg|Sampler board, preamp side
+Tektronix-S4-sampler-board-preamp.jpg | Sampler board, preamp side
-Tektronix-S4-sampler-board-hybrid.jpg|Sampler board, disassembled with parts orientation
+Tektronix-S4-sampler-board-hybrid.jpg | Sampler board, disassembled with parts orientation
-Tektronix-S4-hybrid-internal.jpg|Microphotograph of sampler hybrid
+Tektronix-S4-hybrid-internal.jpg | Microphotograph of sampler hybrid
-Tek s-4 in 7s11.jpg|S-4 in [[7S11]]
+S-4_B15_prototype.JPG | S-4 B-prototype, no difference to standard S-4
-s11-s4.jpg||S-4 in [[7S11]]
+Tek s-4 in 7s11.jpg | S-4 in [[7S11]]
+s11-s4.jpg | S-4 in [[7S11]]
 </gallery>
 [[Category:7000 and 3S series sampling heads]]