In 1946 as Howard Vollum was wrapping up the design of the 511, the Directors of Tektronix decided to introduce a smaller and less complicated product to be able to more easily ramp up manufacturing.  Howard had designed a square wave generator to test his oscilloscope so they introduced this as the Type 101 Video Calibrator.  They built a total of 10 instruments and sold none!  Tektronix first product was a flop.  However, it served its purpose to get manufacturing ready for the Type 511 oscilloscope.  Later the Type 101 Video Calibrator was replaced with the Type 104 Square Wave Generator which had modest sales.

This photo is of Howard Vollum with the Type 101 Video Calibrator on the left and the Type 511 Oscilloscope on the right.  This is the first version of the 511 as noted by the external graticule light and the single sweep speed knob.

At the museum we have both the Type 101 Video Calibrator and the first version of the Type 511 Oscilloscope operational and prominently displayed as you enter.  The serial number of the Type 101 is 11461 which represents November 1946 #1.  This is the very first Tektronix product manufactured!  The serial number of the Type 511 Oscilloscope is 441 so it was the 340th product manufactured.

At the museum we also have a front panel for a 511 that appears to be hand drilled with a serial number 101 which would make it possibly from the very first 511 scope manufactured!

The 511 was very well received and the small Hawthorn facility had to add a swing and then grave shift and even with 3 full shifts running the lead time stretched out to over 6 months.

The 511 was designed for medium and high frequency work but did not effectively work with frequencies below 60 Hz.  Other weaknesses included lack of sufficient vertical gain, the inability to see the trigger portion of the waveform, and the lack of voltage regulation.  The first enhancement was to add a delay line which could be installed as an option.  The second enhancement was to add voltage regulation to the power supply.  Improving the lower bandwidth and more vertical gain became the basis for the follow-on Type 512 Oscilloscope.