S-3

The S-3 sampling head is a plug-in head for use with the 7000 series sampling plug-ins or with the Type 3S2, 3S5, or 3S6 samplers. The plug-in includes a permanently attached 1x probe with the sampling bridge enclosed in the probe.

The input rise time is specified as less than 350ps for the 1x probe, less than 400ps with the optional 10x attenuator tip, and less than 500ps with the 100x attenuator tip. The maximum operating signal voltage is 2Vp-p. The S-3 does not provide a trigger pickoff for internal triggering. An offset voltage of either +/- 1V or +/- 2V can be selected via a toggle switch on the front panel.

Input Characteristics

The probe tip input is equivalent to 100k resistor in parallel with about 2.3pF capacitance at low frequency. With the 10x or 100x attenuator tips, the probe input is equivalent to 1M paralleled with 2pF or 1.7pF, respectively.

Differences between S-3 and S-3A

The S-3A sampling head has a 10x improvement in baseline shift due to cable flexing. All other specifications are identical to the ordinary S-3. The major differences in design involves the gate board in the box part of the probe, but some changes are also made to the circuits in the body of the probe.

Difference between the S-3 and the P6038

The S-3 probe contains a compensated attenuator before the sampling bridge. The P6038 does not. The S-3 probe has a JFET buffer between the holding cap and the probe cable. The P6038 does not.

Repair of Sampling Diodes

Individuals have reported success in replacing the S-3 sampling diodes with Agilent matched pair Schottky diodes.

• Tektronix S-3 Manual (DjVu)
• Tektronix S-3 Manual (PDF)

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  S-3A attenuator

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  S-3A probe

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  S-3A probe internal

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  S-3A probe internal

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  S-3A strobe board