4S2

The Tektronix 4S2 is a sampling vertical plug-in for the 661. Unlike the 4S1, the 4S2's signal path does not contain a delay line between the input connector and the sampler. This has the advantage of maintaining higher pulse fidelity and thus higher bandwidth. It has the disadvantage of making it impossible to see the leading edge of the triggering event unless a pre-trigger is used.

• Tektronix 4S2A Manual (PDF)

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  42SA sampler schematic

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  42SA pulse generator schematic