The Tektronix 176 is a pulsed high-current test fixture for the model 576 curve tracer.
The 176 can be considered a more modern replacement for the 175. Both can supply collector currents up to 200 A.
The 175 uses a rectified mains-frequency transformer secondary current to supply the collector current to the device under test. In contrast, the 176 supplies the collector current by passing stored charge through an SCR. This pulsed technique allows the 176 to measure points far from the origin of the I-V curve while keeping the instrument compact and light and the minimizing thermal effects in the device under test.
The 176 weighs 13 pounds (6 kg), whereas the 175 weighs 84 pounds (38 kg. The 176 has a cooling fan, as does the 175 (for different reasons).
Peak collector supply current is 200A, peak base supply current is 20A.