The 182T is a general-purpose oscilloscope display mainframe. Supported plug-ins (per the 8557A manual) are 8557A and 8558B Spectrum Analyzers, 8755 Swept Amplitude Analyzer, and 1800-series time domain plug-ins (such as 1801A and 1821A).
The 18xT models are oriented towards spectrum analyzer support by providing connectors on the rear panel for X-Y recorders.
Model 182T differs from the other 18xT models in that it has a display that is 29% wider and taller than a typical 10×8 cm display (the graticule divisions are 1.29 cm, instead of the more common 1 cm).
Below is shown a 182T with an 8557A plug-in installed. Note that the panel marking is “182T Display”, rather than “182T Oscilloscope”.