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Larson Davis 2221 Technical Reference Manual

Manual is about: Microphone Preamplifier Power Supply

Summary of 2221

  • Page 1

    Model 2221 microphone preamplifier power supply technical reference manual.

  • Page 2: Model 2221

    Model 2221 microphone preamplifier power supply technical reference manual larson davis, a division of pcb piezotronics, inc. 1681 west 820 north provo, ut 84601-1341 24 hour hotline: (716) 926-8243 toll free (us): (888) 258-3222 www.Larsondavis.Com i2221.01 rev g.

  • Page 3: Copyright

    Copyright copyright 2009 by pcb piezotronics, inc. This manual is copyrighted, with all rights reserved. The manual may not be copied in whole or in part for any use without prior written consent of pcb piezotronics, inc. Disclaimer the following paragraph does not apply in any state or country wher...

  • Page 4: Recycling

    Record of serial number and purchase date model 2221 serial number: ______________ purchase date: __________________ recycling pcb piezotronics, inc. Is an environmentally friendly organization and encourages our customers to be environmentally conscious. When this product reaches its end of life, p...

  • Page 5: Table of Contents

    Table of contents i-i table of contents chapter 1 introduction 1-1 about this manual ........................................................1-1 features........................................................................1-2 unpacking and inspection.............................................1-...

  • Page 6: A-1

    I-ii table of contents: ac signal output cable.......................................................................3-3 operation ..................................................................... 3-3 switch on ........................................................................................

  • Page 7

    Table of contents i-iii length ..................................................................................................A-5 weight ..........................................................................................A-6 connectors ..........................................................

  • Page 8: List of Figures

    Ii-i list of figures introduction 1-1 description 2-1 model 2221............................................................................ 2-1 2221 controls ........................................................................ 2-2 operation 3-1 accessing battery compartment .......................

  • Page 9: About This Manual

    Introduction 1-1 c h a p t e r 1 introduction welcome to the larson davis model 2221 microphone preamplifier power supply. The model 2221 provides power for a microphone preamplifier, a microphone bias voltage of 200 v for use with traditional air condenser microphones (which can be switched off for...

  • Page 10: Features

    1-2 features: features the larson davis model 2221 microphone power supply has the following features: • single channel power and amplification for precision microphone preamplifiers • internal batteries for portable operation • 0 and 200 microphone bias voltages • selectable flat (z), a- and c-weig...

  • Page 11: Unpacking and Inspection

    Unpacking and inspection: 1-3 unpacking and inspection your model 2221 has been shipped in protective packaging. Please verify the package contains the items listed below and retain the shipping container for safe shipment at a future date. Report any damage or shortage immediately to larson davis, ...

  • Page 12

    1-4 accessories and optional equipment: • exaxxx microphone extension cable, 7-pin lemo (the xxx indicates length in feet) • cbl097 cable with 7-pin lemo to bnc plug, 6’ long • pra951-2 and prm951-4 current sources permitting icp ™ accelerometers to be used with the model 2221. • cal200 and cal250 a...

  • Page 13: General Description

    Description 2-1 c h a p t e r 2 description the physical description of the model 2221 is presented in this chapter. This includes a description of the front panel keys and their functions, input and output connectors, instrument controls and the functions of the led indicators. Operational informat...

  • Page 14

    2-2 general description: figure 2-2 2221 controls on/off switch increase gain decrease gain select microphone bias voltage reset overload ac signal output preamplifier input external power input select frequency external power led indicator weighting battery voltage led indicators vernier gain adjus...

  • Page 15: Connectors

    Connectors: 2-3 connectors preamplifier input lemo epg.1b.307 7-pin female pin connections ac output bnc female external dc power input 2.5 x 5.5 mm coaxial connector, center positive (external dc voltage range: 10.5 to 30 v) pin signal 1 no connection 2 signal ground 3 microphone polarization volta...

  • Page 17: Led Indicators

    Led indicators: 2-5 led indicators overload flashing of the overload led indicates a steady input overload. When the input voltage drops below the overload level, the overload led will remain illuminated (latched on) until reset. Signal present the signal led is illuminated when the output signal ex...

  • Page 18

    2-6 battery compartment: door as shown below. The battery polarity is indicated in the bottom of the compartment..

  • Page 19: Powering The Model 2221

    Operation 3-1 c h a p t e r 3 operation this chapter presents a detailed description of the operation of the model 2221. This includes the methods available for providing power, connecting input and output cables, parameter selection and adjusting the gain to obtain the best measurement. Powering th...

  • Page 20: External Battery Or Dc Power

    3-2 powering the model 2221 figure 3-1 accessing battery compartment the internal battery voltage is indicated by one of four leds as described in the section “external dc power input” on page 2-3. If no led is illuminated, the battery voltage is less than 5.5 volts. External battery or dc power not...

  • Page 21: Cable Connections

    Operation 3-3 cable connections signal input cable caution:be sure that all connections in the signal path are made prior to turning on the system power. Connect the microphone preamplifier cable to the 7-pin lemo connector on the front of the case. The length of the cable will affect the frequency ...

  • Page 22

    3-4 operation microphone bias voltage the bias voltage should be set to zero when using a prepolarized (electret) microphone and 200 v when using a traditional air condenser microphone. The microphone bias voltage is either on, providing a highly stable level of 200 vdc, or off. Pressing the microph...

  • Page 23

    Operation 3-5 gain adjustment for best measurement the signal led will be illuminated when the input signal level is above 45 mv. The higher the level, the brighter the led will be. When measuring fairly stable signals, it is recommended to increase the gain until an overload is indicated, reduce th...

  • Page 24: Electrical Specifications

    Technical specifications a-1 a p p e n d i x a technical specifications the technical specifications in this chapter are subject to change without notice. Please refer to calibration and test results for data on a specific unit. Electrical specifications all values are given at 20 °c, 50% r.H., 12 v...

  • Page 25: Frequency Response

    A-2 electrical specifications maximum output current 25 ma overload level (input or output) positive and negative overload detection: ± 16.5 volt peak output slew rate 10 volt/ μs microphone bias voltage 0 and 200 volt ( ± 0.25 v ) note: led flashes for 40 seconds while microphone bias voltage is st...

  • Page 26: Output Noise

    Electrical specifications a-3 output noise the output noise is measured over the frequency range 20 hz to 20 khz, with the input shorted. Cable driving capability the values presented below correspond to a cable having a capacitance of 30 pf/ft. A-weight 63 hz to 20 khz (± 0.3 db ) 10 hz to 50 hz (±...

  • Page 27: Indicators

    A-4 indicators indicators overload instantaneous (blinking led) latched (steady led) - reset on keypad output signal led illuminated for output signals > 45 mv battery level power supply battery power six aa batteries 40 hours of continuous operation with the prm902 microphone preamplifier 1,000 9.5...

  • Page 28: Mechanical

    Mechanical a-5 battery level indicator (4 leds) standby performance uses no power from internal or external batteries when switched off. External 12 v battery or ac adaptor external dc voltage range: 10.5 to 30 v note: the model 2221 will run on external dc voltage down to 6 volts, but will draw pow...

  • Page 29: Weight

    A-6 mechanical weight 425 grams (15 oz.) with six aa cells connectors input lemo epg.1b.307 7-pin female pin connections output bnc female pin signal 1 no connection 2 signal ground 3 microphone polarization voltage 0 or 200 volts 4 signal input 5 no connection 6 power supply positive voltage + 18 v...

  • Page 30: Environmental

    Environmental a-7 environmental operating temperature range - 40 to + 60 °c (- 40 to +140 °f) operating humidity range 0 to 90% rh non-condensing temperature sensitivity @ 1 khz from - 40 to + 60 °c (- 40 to +140 °f) humidity sensitivity @ 1 khz from 0 to 90% rh non-condensing at 40 °c (104 °f) elec...

  • Page 31: United States

    A-8 electromagnetic compatibility •iec61000-4-6:2008 immunity to rf conducted line disturbances. 10 v, 1 khz 80% am from 150 khz to 80 mhz. •iec61000-4-8:2001 power frequency magnetic field immunity. 80 a/m. 50/60 hz. •cispr 11:2009: industrial, scientific and medical (ism) radio-frequency equipment...

  • Page 32: Index

    Index a accessories .................................................................................................................................. 1-3 b battery compartment ........................................................................................................................ 2-...

  • Page 33

    I indicators ............................................................................................................................. A-3,a-4 inspection..................................................................................................................................... 1-3 l led...

  • Page 34

    T technical support ......................................................................................................................... I-2 u unpacking.................................................................................................................................... 1-3.

  • Page 35

    Total customer satisfaction guaranteed 3425 walden avenue, depew ny usa 14043 phone: 716-926-8243 toll free: 888-258-3222 larsondavis.Com fax: 716-926-8215.