The Type 513 oscilloscope was introduced in 1950 and was in production 5 years.  A 513D model which included a single-ended 40 L-C stage delay line was also available. The 513 utilized a distributed amplifier to achieve a flat bandwidth from DC to 20 MHz.

This advanced information for the 513 appeared in the March 1950 Northwest Electronics World magazine (really a 12 page flyer).

These two photos are from a Tektronix Photo Album, date unknown.

We have a Type 513D oscilloscope on display at the museum.

This March 30, 1955 memo discusses the obsolescence of the Type 513 oscilloscope.  Click on the image to view the PDF.