Tektronix Oscilloscope history
type 465 tektronix oscilloscope, popular analog oscilloscope during 1980s
vollum , murdock went on found tektronix, first manufacturer of calibrated oscilloscopes (which included graticule on screen , produced plots calibrated scales on axes of screen). later developments tektronix included development of multiple-trace oscilloscopes comparing signals either time-multiplexing (via chopping or trace alternation) or presence of multiple electron guns in tube. in 1963, tektronix introduced direct view bistable storage tube (dvbst), allowed observing single pulse waveforms rather (as previously) repeating wave forms. using micro-channel plates, variety of secondary-emission electron multiplier inside crt , behind faceplate, advanced analog oscilloscopes (for example, tek 7104 mainframe) display visible trace (or allow photography) of single-shot event when running @ extremely fast sweep speeds. oscilloscope went 1 ghz.
in vacuum-tube oscilloscopes made tektronix, vertical amplifier s delay line long frame, l-shaped space reasons, carried several dozen discrete inductors , corresponding number of low-capacitance adjustable ( trimmer ) cylindrical capacitors. these oscilloscopes had plug-in vertical input channels. adjusting delay line capacitors, high-pressure gas-filled mercury-wetted reed switch created extremely fast-rise pulses went directly later stages of vertical amplifier. fast sweep, misadjustment created dip or bump, , touching capacitor made local part of waveform change. adjusting capacitor made bump disappear. eventually, flat top resulted.
vacuum-tube output stages in wideband oscilloscopes used radio transmitting tubes, consumed lot of power. picofarads of capacitance ground limited bandwidth. better design, called distributed amplifier, used multiple tubes, inputs (control grids) connected along tapped l-c delay line, tubes input capacitances became part of delay line. well, outputs (plates/anodes) likewise connected tapped delay line, output feeding deflection plates. (this amplifier push-pull, there 4 delay lines, 2 input, , 2 output.)
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