561

The Type 561 is an oscilloscope that take one 2-series or 3-series vertical plug-in and one 2-series or 3-series horizontal plug-in. The plug-ins directly drive the horizontal and vertical deflection plates of the CRT. The 561 is the most common of the 560-series scopes. There is an RM561, introduced in 1961, the rackmount version of the 561. The 561A was introduced in 1962.

There is also a 561S, which is used with special plug-ins such as the 3A1S and 3B1S. The 561S system has a vertical bandwidth of 25MHz instead of the standard 561's bandwidth of 10MHz. The 561S uses a special CRT with higher sensitivity but smaller deflection limits.

Tek 561S
Tek 3A1S and 3B1S