The Tektronix 519 is a 1 GHz oscilloscope introduced in 1961.  The 1 GHz bandwidth was achieved by driving the plates of the CRT directly with no vertical amplifier.  This achieves a vertical deflection of ~10 V/cm.  To achieve the 1 GHz bandwidth Tektronix also made a unique 125 Ω GR-874 connector which is not compatible with the commercial 50 Ω GR-874 connector.  The 519 also came standard with a camera mount bezel.  Only the center of the CRT was guaranteed for the bandwidth so the non-displayed portion of the CRT is covered by the bezel.  Each bezel has the specifications for the CRT.  The 519 on display at the museum has a vertical sensitivity of 9.46V/cm and a risetime of 300 pS.

 

The museum does not have any 125 Ω GR-874 connectors so we are driving the oscilloscope with a Type 106 Square-Wave Generator through a 50 Ω coax with clip leads to the input.  This mismatch in termination provides some nice reflections for the display.  The museum also has a 519 CRT on display as well.

The delay line is very unique as it is a custom rigid coax with a delay of only 45 nS.  This delay line, along with the longer CRT and large transformer required a larger and more robust mechanical package.

Stan Griffiths, one of the two museum founders, calibrated 519 oscilloscopes early in his career at Tektronix.