The Tektronix S-6 sampling head

This 1960s vintage oscilloscope sampling head is able to acquire 30ps rise time signals. Its loop-through input construction makes it ideal for TDR measurements. On the photograph below, the two signal connectors are at the top, and the sampling pulse is applied differentially to the two connectors at the bottom.

Photograph of S-6 sampling head


Schematic diagram of S-6 sampling head


LTspice simulation schematic diagram


LTspice simulation results