The Tektronix Type N is a sampling plug-in for 500-series scopes. It was the first sampler produced by Tektronix. The risetime is specified to be under 600 picoseconds. The Type N is a complete sampling subsystem, using the 500-series oscilloscope just as a power supply and a display. The oscilloscope is operated in X-Y mode and gets its horizontal signal from the Type N plug-in instead of from the scope's sweep circuitry. The input connector is a 50-ohm GR-874. The Type N was introduced in 1960, superseded by the Type 661 Sampling Oscilloscope system a year later, and discontinued in 1964, making it the shortest-lived plug-in.
The sampling circuit of the Type N is primitive. It uses a single diode, the "interrogate diode", D5480. The strobe pulse is added to the input signal using a passive summing circuit. Consequently, the amplitude of the kick-out pulse from the input is high, about 150mV.
The vertical scale of the Type N is fixed 10mV/cm. The Type N is one of the few Tektronix plug-ins with fixed vertical gain. In practice, attenuators can be placed in the signal path, external to the Type N, to achieve the desired sensitivity. This also has the effect of attenuating the kick-out pulse seen by the device under test.
For calibration of the timebase of the Type N, the 013-028 Timing Standard was produced.
- Tektronix Type N Manual without schematics (BAMA)
- Tektronix Type N Schematics (PDF)
- Tektronix Type N Factory Calibration Procedure (PDF)
- Tektronix Type N Manual Complete (PDF)