155-0076-00
The Tektronix 155-0076-00 (M94) is a Tek-made input protection and probe logic integrated circuit in a 16-pin minipac package, designed by John Addis.
Probe Readout Ring Decoder
The M94 has a circuit for decoding the probe attenuation factor based on the probe readout pin. The probe readout pin contacts the readout ring on the probe input of the scope. The readout ring is pulled up to 5 volts by a 5 kΩ resistor.