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Dorrough 40-A

Discussion in 'Metering VU' started by audiokid, Oct 25, 2011.

  1. audiokid

    audiokid Chris Staff Resource Member

    Mar 20, 2000
    Prince George, BC
    Home Page:

    TheB 40-AB has a scale showing 14 dB headroom in 1dB steps from 14 to -25.

    The 40-A series Loudness Meters are considered the standard models with built-in power supplies. They are the large ARC-Style, three color LED display single channel meters.

    The Remote Control (RW-100) is now available for these units and will access the functions of phase correlation display, peak hold, sumdiff, and activate a reference mode allowing for accurate 0 setting within .1dB. A red LED notification alarm is present on the front of the unit.

    For Models 40-A, 10-A, 20-A, 12-A, 240-A, 280-A, 380-A, 400-A.

    Input Parameters
    Input Z : 20k Ohm balanced, 10k Ohm single-ended, - 2%
    *CM : 80 dB at 60 Hz, 60 dB at 20 kHz (balanced mode)
    *Input Sensitivity : -10 dB for full-scale display
    *Maximum Input Level : 24 dB before clipping

    BSignal Path ParametersB
    *Signal Path Bandwidth : 10 Hz - 25 kHz, - .25 dB
    *Signal Path Distortion : Less than 1% THD at 1 kHz, 24 dB input
    *Sum Error : Less than 0.1 dB at 1 kHz
    ยค Difference Error : Less than 0.1 dB at 1 kHz

    Display Parameters (All parameters apply to AVERAGE, PEAK, and PEAK HOLD display elements.)
    *Display Resolution : 40 LEDs, 1 dBLED except model 60D, - 0.25 dB.
    *Step Size Error : - 0.25 dB
    *Absolute Error :
    - Full Scale -39 dBu : - 0.25 dB model A,B,C
    - Full Scale -59 dBu : - 0.25 dB model D
    *Drift : - 0.25 dB
    *Average Time Constant : 600 mS, - 6%
    *Peak Acquistion Period : 10 uS, to full-scale, sine input 25kHz
    *Peak Attack Period : Virtually Instantaneous
    *Peak Decay Period : 180 mS, from full-scale to all LEDs off (models A, B, C)
    *Display Update Rate : Approximately 10 mS
    *Display Duty Cycle : Display Time, AVERAGE, PEAK HOLD - 75%
    Display Time, PEAK - 100%

    BMiscellaneous ParametersB
    *Power Supply Input Range : 117237 VAC RMS, -20% to 10%, 50-60 Hz
    *Calibration Controls : None needed
    *User Controls :
    LeftRight input sensitivity
    Option DIP Switch
    A) Peak Auto ON
    B) Difference Mode ONOFF
    C) Over Level Alarm ENABLE
    D) Under Level Alarm ENABLE
    E) Auto ARMP

    *User Port :
    BDB-9 ConnectorB
    A) Alarm relay closure contacts 1 form C, 1A, 30V AC or DC
    B) Mode control switch (user supplied)
    C) PEAK function switch (user supplied)

    Attached Files:

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