Tektronix 3B4 Time Base Plug-In (1969)

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Quick Specifications / Photos
Detailed Specifications
Operating Instructions
Misc. Part Numbers

Samples of e-Bay Prices
Tektronix Catalog CostLow BidHigh Bidaverage
$450 (1969)
$495 (1974)
...
$39.00 12/7/02 #1922306174 golana600
$14.99 1/22/03 #3108265973 ridgeeq@erols.com (untested) (1 bid)
$9.95 8/20/04 #3833938540 sams995 (1 bid) (untested)

QUICK SPECS / PHOTOS
  • 50 ns/div to 5 s/div
  • X50 Direct Reading Magnifier
  • Triggering to 20 MHz
  • Single Sweep Operation
  • Calibrated External Horizontal Input
  • Net Weight - 5 lb
  • Tunnel Diode Trigger Circuit


    SPECIFICATIONS

    The Type 3B4 Time Base Plug-in unit is designed to be used primarily with the Tektronix Type 561A Oscilloscope system; however, it can also be used with the other 560-Series systems that use 3B-Series plug-in units such as the Type 564 and Type 567. As part of an oscilloscope system, the Type 3B4 is used as an accurate time base generator or as a calibrated amplifier for externally generated deflection signals.

    The Type 3B4 provides calibrated sweep rates from 0.05 μsec/div to 5 sec/div in 25 calibrated steps. A five-step, direct-reading magnification feature provides magnification up to 40 X or 50 X, depending on the sweep rate to which magnification is applied. When the Type 3B4 is used as an amplifier for externally generated deflection signals, the magnifier provides five steps of deflection sensitivity, from 0.2 volts/div to 5 volts/div. In addition, a variable control provides uncalibrated sweep rates and deflection sensitivities between the calibrated steps. By using the variable control, uncalibrated sweep rates from 0.05 μsec/div to approximately 12.5 sec/div and deflection sensitivities from 0.2 volts/div to approximately 12.5 volts/div are available. Uncalibrated operation is indicated by a neon lamp.

    Triggering

    Facilities

    TIME/DIV Switch 0.2 μsec/div to 5 sec/div in 23 steps, 1, 2, 5 sequence. The calibration accuracy (unmagnified) is ±3% from 0.2 μsec/div to 2 sec/div; ±5% at 5 sec/div.
    MAGNIFIER Control Provides direct readout magnification of the sweep (up to 50 X). The magnifier also provides the 0.05 and 0.1 μsec/div sweep rates. Magnified sweep accuracy, ±5% (exception: 5 sec/div). Magnified sweep registration, ±1 minor division.
    TRIGGER MODE Switch  Free Run, Auto, Normal, and Single Sweep
    SLOPE Switch + or -
    COUPLING Switch Ac, Ac Low-Frequency Reject, and Dc
    SOURCE Switch Internal, Line, External, and External ÷ 10

    TRIGGERING LEVEL Control Voltage Range (external triggering)
    SOURCECOUPLINGVoltage Range
    TypicalMinimum
    EXTAC, DC or  
    AC LF REJ± 19 v± 15 v
    EXT ÷ 10AC, DC or± 190 v 
    AC LF REJ ± 150 v

    TRIGGERING SENSITIVITY

    SOURCEVoltage Range
    ACAC LF REJDC
    INT1 minor division of deflection 30 Hz to 20 MHz. Outside these limits requires larger triggering signal. 1 minor division of deflection 30 kHz to 20 MHz. Outside these limits requires larger triggering signal. 1 minor division of deflection dc to 20 MHz (with trace vertically centered). Above 20 MHz requires larger triggering signal.
    EXT0.2v 30 Hz to 20 MHz. Outside these limits requires larger triggering signal. 0.2v 30 kHz to 20 MHz. Outside these limits requires larger triggering signal. 0.2v dc to 20 MHz (with trace vertically centered). Above 20 MHz requires larger triggering signal.


    EXTERNAL HORIZONTAL INPUT
    0.2 V/div to 5 V/div in 5 calibrated steps (max input ±20V); accuracy, when plug-in unit is matched to oscilloscope, is within 3%. The External Input Amplifier is DC coupled.

    (excerpt from Tektronix® Instruction Manual)

    OPERATING INSTRUCTIONS

    FIRST-TIME OPERATION

    The following control and switch settings for the Type 3B4 can be used for a wide range of measurements. The operating conditions established by these settings also provide a starting point for the operator who is learning to use the instrument.

    TRIGGER MODEAUTO
    COUPLINGAC
    SOURCEINT
    VARIABLE (TIME/DIV)CALIB (fully clockwise)
    MAGNIFIERLocked to TIME/DIV switch

    The Type 3B4 now provides the time base for measurements of vertical deflection signals above about 20 Hz. In many cases, only the TIME/DIV switch and the TRIGGERING LEVEL control require readjustment when progressing from one measurement to the next.

    TIME/DIV OR HORIZONTAL VOLTS/DIV

    The Time Base has 23 calibrated sweep rates ranging from 0.2 μsec/div to 5 sec/div (unmagnified). The number opposite the dot on the MAGNIFIER knob indicates the sweep time per division as long as the VARIABLE control is in the CALIB position. The unmagnified sweep rate value being used appears between the two black lines on the clear plastic flange of the TIME/DIV control. The CARIABLE control and MAGNIFIER switch, used in conjunction with the TIME/DIV switch, permit the sweep rate to be varied continuously between 50 nsec/div and about 12.5 sec/div.

    When the flange is positioned so that the two heavy black lines bracket the EXT HORIZ IN position the horizontal amplifier input is connected to the EXT HORIZ IN connector and accepts external horizontal deflection signals. In this mode of operation, five ranges of horizontal deflection sensitivity are available. The five sensitivity ranges are from 0.2 volts/div to 5 volts/div.

    To position the TIME/DIV switch to the EXT HORIZ IN position, turn the MAGNIFIER knob until the dot on the knob is positioned between the two black lines on the clear plastic flange. Turn the knob until the two black lines on the flange bracket the position marked "EXT HORIZ IN". The external horizontal deflection sensitivity may now be selected by pulling the MAGNIFIER knob outward to unlock it, then, while holding the knob out, turn it to the desired volt/div position.

    MAGNIFIER

    The sweep ranges between 5 sec/div and 2 μsec/div can be magnified up to 40X or 50X in 5 steps. The degree of magnification is the ratio between the indicated magnified rate (number opposite the dot on the skirt of the MAGNIFIED knob) and the indicated unmagnified rate (number bracketed by two black lines on the clear plastic flange). Since the magnified display rate is always direct reading, it is seldom necessary to determine the actual magnifying factor used.

    (excerpt from Tektronix® Instruction Manual)

    MISC PART NUMBERS
    Knobs
    331-132Dial, window knob for TIME/DIV
    366-038Knob, small red, VARIABLE
    366-138Knob, charcoal, POSITION
    366-173Knob, charcoal, TRIGGER MODE
    366-173Knob, charcoal, TRIGGERING LEVEL
    366-215Knob for 3-lever switches
    366-255Knob, small red, FINE Position
    366-269Knob, large charcoal, TIME/CM
    Pots/Switches
    R16311-2172 x 1 Meg Var TRIGGERING LEVEL
    R229311-48120K and 30K dual pot w/ SW229 VARIABLE
    R402311-31520K pot SWEEP CAL
    R406/R409311-478150K / 1 meg dual pot POSITION
    SW10260-472Switch, lever, SLOPE
    SW130260-263Sw, rotary TRIGGER MODE
    SW135260-518Switch, push-pull w/ red light, MAGNIFIER
    SW160260-624Sw, rotary, TIME/DIV
    SW5260-615Switch, lever, SOURCE
    SW8260-594Switch, lever, COUPLING
    Tubes
    V161154-2786DL8
    V173154-1876DJ8
    V24154-1876DJ8
    V444154-3407119