The Tektronix S-2 Sampling Head plug-in provides a single GR-874 50 Ω input with a 75 ps risetime.
The S-2 can be used in the 7000 series and 3S series of sampling plug-ins. It provides an internal trigger pickoff signal for internal triggering. Noise is specified as less than 10 mV.
When the S-2 was first introduced, the rise-time specification was 50 ps, but that was not achieved in practice, so the rise-time specification was revised to be 75 ps.
The interface between the GR-874 connector and the printed circuit board is described in US Patent 3,426,311.
|Rise time||75 ps|
|Bandwidth||4.66 GHz eq.|
|Input voltage||−1 to +1 V (max. −5 to +5)|
The input should always be terminated when not in use because the sampling diodes are easily damaged by excessive inputs or static discharge. See that article for possible replacements.
S-52 and S-2 give 76 ps rise-time together