Tektronix 3A7 Differential Comparator (1969)

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BAMA Free 3A7 Manual and Schematic Download Site
This is a MIL manual
Tektronix Catalog CostLow BidHigh Bidaverage
$695 (1969)
$750 (1973)
$15.50 3/22/02 #1713879926 rkcooper

  • Bandwidth : DC to 10 MHz
  • Sensitivity : 1 mV/div to 50 V/div

    The Type 3A7 Differential Comparator plug-in unit is designed for use with all 560-Series oscilloscopes (except the Type 560 itself) and their rackmount equivalents. The unit can also be used in conjunction with a Type 129 Plug-In Power Supply.

    The primary operating modes for the unit are: (1)conventional amplifier, (2) differential amplifier, or (3) calibrated differential comparator.

    As a conventional amplifier, two switches select the calibrated deflection factors from 1 mV/div to 50 V/div. The MILLIVOLTS/DIV switch changes the amplifier gain in a 1-2-5 sequence from 1 mV/div to 50 V/div. The input attenuator switch provides decade attenuation from 1A to 1000X. Bandpass is greater than 10MHz at a deflection factor of 50 mV/div; at 1 mV/div bandpass is greater than 4 MHz.

    As a differential amplifier, common-mode rejection ratio (CMRR) exceeds 20,000:1 fron dc to 20 kHz and 500:1 at 500 kHz. CMRR is defined as the ratio of common-mode input voltage to differential voltage on the screen (vertical defletion X mV/div setting). A ratio of betterr than 20,000:1 at dc and low frequencies allows measurement of signals less than 1 mV in amplitude on ±11 common-mode signals.

    As a calibrated differential comparator, the slideback technique is used to make precise voltage measurements. The internal highly-accurate ±11-volt comparison voltage (Vc) is applied differentially to the Type 3A7 input stage. With a dynamic range or ±11 volts and a maximum sensitivity of 1 mV/div, the effective screen height is ±11,000 div (11V ÷ 1 mV). Measurement readout resolution is 100 µV/mm or 0.001% (100 µV ÷ 11V).

    (excerpt from Tektronix® Technical Manual)