White Instruments 200 User manual

5 January 2005 –This contact update page has been added to the
Acrobat document you have downloaded. Please disregard any contact
information printed within the document.
Our Mailing and Shipping Address:
White Instruments Div. C Van R, Inc.
1514 Ed Bluestein Blvd., Suite 201 (for U.S. Mail)
Austin, TX 78721 U.S.A.
Phone: [phone]
Fax: [phone]
Main Email Address: [email protected]
World Wide Web Site: http://www.whiteinstruments.com/
Note: Repairs and packages should be shipped to Suite 202

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Dear System 200 Owner:
CONGRATULATIONS’. You have purchased the most advanced Real Time Analysis System ever
offered to the Audio Professional in this price range. As you become more familiar with its functions,
we think you will agree that its performance and features approach and often exceed those of analyzers
costing thousands of dollars more. We have done everything possible to make the operation of your new
System 200 Signal Analyzer simple and cybernetically human. We sincerely hope you will take the time
to thoroughly read and digest this manual as you become familiar with the System 200. If you have any
questions concerning its operation or specifications, please feel free to write me or call me any time.
Have a good day.
IMPORTANT NOTICE-REGISTRATION OF SYSTEM 200 SIGNAL ANALYZERS:
Features and functions of the System 200 Signal Analyzer are a result of its running COMPUTER
PROGRAMS which tell it what to do as opposed to Hard Wired Circuitry.
Like any computer, these programs need to be maintained from time to time in order to increase their
efficiency, correct errors, and add new routines.
White Instruments, Inc. intends to keep a file on each System 200 Signal Analyzer shipped.
It is therefore EXTREMELY IMPORTANT that we have current ownership information for each unit.
This information should include:
1. Owner’s Name
2. Owner’s Mailing Address
3. Owner’s Shipping Address
4. Owner’s Telephone Number
5. System 200 Mainframe Serial Number
If you are the original owner, please fill out and return the OWNER’S SERVICE CARD packed with
your analyzer. If you sell the unit, please be so kind as to pass along this manual to the new owner and
send us the above information. Also, please let us know if you should change
your address or telephone number.
Your cooperation in this matter will assure your receiving application bulletins, notification of option
availability and smooth system updating.

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Dear System 200 Owner:............................................................................................................................ 1
IMPORTANT NOTICE -REGISTRATION OF SYSTEM 200 SIGNAL ANALYZERS:...................... 1
1 UNPACKING:.................................................................................................................................... 5
1.01 INBOUND INSPECTION AND DAMAGE CLAIMS:............................................................ 5
1.02 INCLUDED WITH YOUR SYSTEM 200 SIGNAL ANALYZER:......................................... 5
1.03 WARRANTY: ............................................................................................................................ 5
2 POWER –CONNECTIONS AND SPECIFICATIONS:................................................................... 7
2.01 IMPORTANT CAUTION.......................................................................................................... 7
2.02 NOMINAL A.C. VOLTAGES AND POWER:......................................................................... 7
2.03 FUSES:........................................................................................................................................ 7
3 INPUT CONNECTIONS:.................................................................................................................. 8
3.01 FRONTPANEL CONNECTIONS:........................................................................................... 8
3.01.01 MICROPHONE INPUT CONNECTOR........................................................................ 8
3.01.02 MICROPHONE POWER............................................................................................... 8
3.01.03 LINE LEVEL INPUT CONNECTOR............................................................................ 9
3.02 REAR PANEL CONNECTIONS:.............................................................................................. 9
3.02.01 LINE LEVEL INPUT CONNECTOR............................................................................ 9
4 OUTPUT CONNECTIONS:............................................................................................................10
4.01 FRONT PANEL CONNECTIONS .......................................................................................... 10
4.01.01 PINK NOISE OUTPUT CONNECTOR ...................................................................... 10
4.01.02 MICROPHONE PREAMP OUTPUT.......................................................................... 10
4.02.01 OSCILLOSCOPE SYNC OUTPUT.............................................................................10
4.02.02 PINK NOISE OUTPUT................................................................................................ 10
4.02.03 OSCILLOSCOPE AND/OR PLOTTER PEAK OUTPUT.......................................... 10
4.02.04 OSCILLOSCOPE AND/OR PLOTTER AVERAGE OUTPUT................................. 10
4.02.05 PLOTTER HORIZONTAL OUTPUT......................................................................... 10
4.02.06 COMNON.....................................................................................................................10
4.02.07 MICROPHONE PREAMP OUTPUT.......................................................................... 11
5 SYSTEM INITIALIZATION:.......................................................................................................... 12
5. 01 GENERAL:...........................................................................................................................12
5.02 INITIALIZATION –THE dBm MODE: ................................................................................. 12
5.03 INITIALIZATION –THE dB/spl MODE:...........................................................................13
6 INPUT LEVELS:.............................................................................................................................. 14
6.01 CONTROL:............................................................................................................................... 14
6.02 RANGE:....................................................................................................................................14
6.03 DYNAMIC RANGE (Processing):...........................................................................................15
6.04 OVER RANGE CONDITION.................................................................................................. 15
6.05 INPUT PREAMP OVERLOAD:.............................................................................................. 15
6.06 UNDER RANGE CONDITION:.............................................................................................. 15
7 PROCESSING MODES:.................................................................................................................. 16
7.01 GENERAL:............................................................................................................................... 16
7.02 AVERAGE MODE:.................................................................................................................. 16
7.03 PEAK MODE:.......................................................................................................................... 17
9 FILTERS AND BANDWIDTH:...................................................................................................... 18
9.01 GENERAL:............................................................................................................................... 18
9.02 200-01-00 OPTION: ONE-THIRD OCTAVE/OCTAVE BAND, THREE-POLE FILTER
SET: 19
9.03 200-02-00 OPTION: ONE-SIXTH OCTAVE, TWO-POLE FILTER SET:...........................20

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9.04 200-03-00 OPTION: ONE-SIXTH OCTAVE, TWO-POLE FILTER SET:...........................21
9.05 OTHER FILTER SETS:...........................................................................................................22
9.06 BANDWIDTH CHANGE KEY:.............................................................................................. 22
9.07 FILTER CARDS, CODES AND JUMPERS:.......................................................................... 22
9.07.01 FILTER CARDS...........................................................................................................22
9.07.02 BANDWIDTH CODE.................................................................................................. 22
9.07.03 DISPLAY POSITION CODES AND JUMPERS ........................................................ 23
10 WEIGHTING................................................................................................................................ 24
10.01 GENERAL............................................................................................................................24
11 LEVEL AND AMPLITUDE DISPLAYS ....................................................................................25
11.01 SPECTRUM DISPLAY........................................................................................................ 25
11. 02 BROADBAND COLUMN:.................................................................................................. 25
11.03 POSITION DISPLAY: ......................................................................................................... 26
11.04 MONITOR DISPLAY:......................................................................................................... 26
11.04.01 LEVEL MODE .............................................................................................................26
11.04.02 TIME MODE................................................................................................................ 26
12 DISPLAY MODES ....................................................................................................................... 27
12.01 DISPLAY MODE CHANGE KEYS:...................................................................................27
15 OSCILLOSCOPE AND PLOTTER FEATURES............................................................................... 39
15.01 GENERAL.................................................................................................................................. 39
15. 02 PLOTTER HOOK-UP............................................................................................................... 40
15.03 OSCILLOSCOPE HOOK-UP:.............................................................................................42
15. 04 PLOT FUNCTION:.............................................................................................................. 43
15. 04. 01 GENERAL................................................................................................................ 43
15.04.02 FORMAT...................................................................................................................... 43
15.04.03 PLOTTING X AND Y AXIS SCALES ....................................................................... 43
15.04.04 PLOTTING DATA: FROM MEMORY........................................................................ 43
15.05 OSCILLOSCOPE MODE: WARNING ............................................................................... 46
15.05.01 GENERAL....................................................................................................................46
15. 05. 02 ENTERING OSCILLOSCOPE MODE ...................................................................46
15.05.03 EXITING THE OSCILLOSCOPE MODE.................................................................. 46
16 CURSORS ....................................................................................................................................47
16.01 GENERAL:...........................................................................................................................47
16.02 VERTICAL CURSOR:......................................................................................................... 47
16.03 HORIZONTAL CURSOR:...................................................................................................47
17 SYSTEM 200 T60 MEASUREMENTS –OPERATING SUMMARY........................................ 48
17. 01 INTRODUCTION................................................................................................................ 50
17.02 BACKGROUND.................................................................................................................. 50
17.03 THEORY OF OPERATION................................................................................................. 50
17.04 START TIME THRESHOLD .............................................................................................. 53
17.05 T60MODE –SELECTION:.................................................................................................. 56
17.06 T60MODE –VERTICAL CURSOR: ...................................................................................58
17.06.01 GENERAL....................................................................................................................58
17.06.02 MANIPULATION –VERTICAL CURSOR............................................................... 59
17.06.03 RESETTING THE ANALYZER TO TAKE A NEW SET OF AVERAGES OF T60
MEASUREMENTS.......................................................................................................................... 60
17.06.04 COUNTING THE NUMBER OF MEASUREMENTS IN AN AVERAGED SERIES
61
17.06.05 ERROR POSSIBILITY –FLASHING VERTICAL CURSOR...................................61

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17.06.06 OTHER VERTICAL CURSOR INDICATIONS......................................................... 61
17.07 MAKING T I’1F4SURElIENTS:......................................................................................... 62
17.07.01 GENERAL....................................................................................................................62
17.07.02 “ARMING” THE ANALYZER FOR A T60 MEASUREMENT................................. 62
17.07.03 T60 MEASUREMENTS USING THE ANALYZER’S BUILT-IN PINK NOISE
SOURCE 62
17.07.04 T60MEASUREMENTS USING AN OUTBOARD EXCITATION SOURCE...........64
17.08 DISPLAYING T60 MEASUREMENTS AND DECAY CURVES...................................... 65
17.08.01 GENERAL......................................................................................................................... 65
17.08.02 THE MONITOR DISPLAY ......................................................................................... 65
17.08.03 STORAGE OSCILLOSCOPE...................................................................................... 66
17.08.04 STRIP CHART RECORDER ....................................................................................... 66
17.09 EXITING THE T
60 NODE:.................................................................................................. 67
17. 10 EFFECTS OF THE ANALYZER ’ s FILTERS, SMOOTHING TIME CONSTANTS AND
PEAK/AVERAGE MODES ON T60 MEASUREMENTS:................................................................. 68
18 SERVICE NOTES ........................................................................................................................ 77
18. 00 Manual Revisions and Additions .......................................................................................... 77
18. 01 Retrofit Procedures ............................................................................................................... 78
18.01.02 Assembly Instructions....................................................................................................... 78
18.02 Performance Tests................................................................................................................. 85
18.02.01 Checkout Procedure ...................................................................................................... 85
18.03 Calibration.............................................................................................................................88
18.03.01 Filter Board Calibration Procedure............................................................................... 88
18.04 Documentation...................................................................................................................... 89
18.04.03 Wiring Diagrams & Connection Tables ....................................................................... 89
18.04.03.12 Calibration Pot Location...........................................................................................89

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1UNPACKING:
1.01 INBOUND INSPECTION AND DAMAGE CLAIMS:
Your System 200 Signal Analyzer has been carefully packaged to avoid damage in shipment. If
the unit has been damaged in shipment, SAVE ALL PACKING MATERIALS and file an
IMMEDIATE claim with the carrier.
Our instruments are shipped with full insurance unless the buyer instructs otherwise under his
self-insurance. Prompt inspection should be made upon delivery and any necessary claims made
against the carrier, NOT White Instruments, Inc.
If your unit is delivered damaged please notify us at once and we will be happy to cooperate in
obtaining repairs or a replacement.
1.02 INCLUDED WITH YOUR SYSTEM 200 SIGNAL ANALYZER:
The following should be packed with your unit:
1. A System 200 Signal Analyzer Mainframe
2. Ordered Accessories and Options, Installed
3. This Instruction Manual
4. A.C. POWER CORD
5. Patch Cord as follows:
0.25” 2-Conductor Phone to XLR Male
Type #A 101381 (see drawing in appendix)
Note: This noise cord is equipped with a 330 ohm resistor between pins 1 & 2 of the XLR
connector. Without this resistor there would be considerable high frequency roll-off of the
signal when the microphone level pink noise is fed to the microphone input. This is due to
the 15 volt microphone powering circuit.
6. One package containing four #10-24 x 0.5” Machine Screws and four Nylon Finishing
Washers
7. The attached Owner Service Card
Please complete and return immediately so that we may keep you continually updated –
Thanks.
1.03 WARRANTY:
1. LIMITED WARRANTY
All our products are guaranteed against defects in materials and workmanship for one year
from date of shipment. Our warranty is limited to repairing or replacing any product which
fails during the warranty period from normal use. White Instruments, Inc. will not be liable
for any damage resulting from the use of this instrument.

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2. DAMAGE IN SHIPMENT
Our instruments are shipped with full insurance unless the buyer instructs otherwise under
his self-insurance. Prompt inspection should be made upon delivery and any necessary
claims made against the carrier. Damage received during shipment is the buyer’s
responsibility. Please notify us at once, and we will cooperate in obtaining repairs or a
replacement.
3. RETURN SHIPMENT
Any instrument returned for repair should be safely packed and shipped PREPAID to us.
Collect shipments WILL NOTBE ACCEPTED unless previously authorized. An
explanation of the type of trouble encountered should accompany the instrument, or be sent
to us separately in writing, or be transmitted by phone. Repairs and checks will be made
promptly. Return will be made collect by the best way, or by the owner’s choice of method.
Address all inquiries to: Our current address found on our web site
http://www.whiteinstruments.com/

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2POWER –CONNECTIONS AND SPECIFICATIONS:
2.01 IMPORTANT CAUTION
BEFORE CONNECTING THE POWER CORD TO THE ANALYZER, CHECK THE MAINS
VOLTAGE AND ADJUST THE POWER SELECTOR SWITCH LOCATED ON THE REAR
PANEL TO THE APPROPRIATE VOLTAGE.
2.02 NOMINAL A.C. VOLTAGES AND POWER:
115 VAC at 50 or 60 Hz –.75 amps
230 VAC at 50 or 60 Hz –.375 amps
2.03 FUSES:
115 VAC = 1.5 amp Slo Blo
230 VAC = 0.75 amp Slo Blo

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3INPUT CONNECTIONS:
3.01 FRONT PANEL CONNECTIONS:
3.01.01 MICROPHONE INPUT CONNECTOR
TYPE: XLR Female
Pin No. 1: Shield
Pin No. 2: Circuit Low or “-“
Pin No. 3: Circuit High or ”+”
Input Impedance: 800 Q, Nominal Transformer Isolated and Balanced.
3.01.02 MICROPHONE POWER
The MICROPHONE INPUT CONNECTOR is equipped with 15 Volt
microphone power. Condenser microphones drawing 1 milliamp or less
current at 15 VDC can be powered directly from the System 200 Signal
Analyzer Mainframe.
Figure 3.01

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3.01.03 LINE LEVEL INPUT CONNECTOR
TYPE: .25” 2-Conductor Phone Jack with Normal Leaf
Tip: Circuit High or ”+” LINE LEVEL INPUT
Ring: See OUTPUT CONNECTIONS (Section 4)
Sleeve: Circuit Common
Input Impedance: 10k ohms, Minimum Unbalanced, Singled-Ended
Please refer to Figure 3.02
When a phone plug is inserted into the front panel LINE LEVEL INPUT
CONNECTOR, the analyzer is switched from the dB/spl MODE to the
dBm MODE.
Figure 3.02
3.02 REAR PANEL CONNECTIONS:
3.02.01 LINE LEVEL INPUT CONNECTOR
TYPE: .25” 2-Conductor Phone Jack
Tip: Circuit High or ”+”
Ring: See OUTPUT CONNECTIONS (Section 4)
Sleeve: Circuit Common
Input Impedance: >10k ohms, Minimum. Unbalanced, Single-Ended
NOTE: When using this INPUT, insert a dummy plug into the front panel
LINE LEVEL INPUT CONNECTOR. If this not done...
1. The analyzer’s PREAMP OUTPUT will be shorted to the LINE LEVEL
INPUT.
2. The analyzer will be in the dB/spL MODE instead of the dBm MODE.
3. See Section 3.01.03 and Figure 3.02

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4OUTPUT CONNECTIONS:
4.01 FRONT PANEL CONNECTIONS
4.01.01 PINK NOISE OUTPUT CONNECTOR
TYPE: .25” 2-Conductor Phone Jack
Tip: Circuit High or ”+”
Line Level Output O.175 V, Nominal
0 ohms, Nominal
Ring: Circuit High or ”+”
Microphone Level Output 0.010 V, Nominal
300 ohms, Nominal
Sleeve: Circuit Common
4.01.02 MICROPHONE PREAMP OUTPUT
Location: Ring ofLINE LEVEL INPUT CONNECTOR
Maximum Operating Level: 7.8 Volt, Nominal
Output Impedance: 0 ohms, Nominal
4.02.01 OSCILLOSCOPE SYNC OUTPUT
TYPE: Barrier Terminal
Function: Supplies Sync to Externally Triggered Oscilloscope.
PLOT MODE: Supplies Pen Lift for Plotter
Please refer to Section 15.
4.02.02 PINK NOISE OUTPUT
TYPE: Barrier Terminal
Function: Line Level Pink Noise Circuit High or ”+”
Level: 0.775 Volt, Nominal
Source Impedance: 0 ohms, Nominal Unbalanced Single-Ended
Connect between terminals PINK NOISE OUT and COMMON.
4.02.03 OSCILLOSCOPE AND/OR PLOTTER PEAK OUTPUT
TYPE: Barrier Terminal
Function: Supplies Peak Amplitude Drive
l. Oscilloscope Input
2. Plotter ”Y” Axis Input
Please refer to Section 15
4.02.04 OSCILLOSCOPE AND/OR PLOTTER AVERAGE OUTPUT
TYPE: Barrier Terminal
Function: Supplies Average Amplitude Drive
l. Oscilloscope Input
2. Plotter ”Y” Axis Input
Please refer to Section 15
4.02.05 PLOTTER HORIZONTAL OUTPUT
TYPE: Barrier Terminal
Function: ”X” Axis Plotter Drive
Please refer to Section 15
4.02.06 COMNON
TYPE: Barrier Terminal
Function: Circuit Common

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4.02.07 MICROPHONE PREAMP OUTPUT
TYPE: .25” 2-Conductor Phone Jack
Location: Rear PanelLINE LEVEL INPUT JACK
Tip: See INPUT CONNECTIONS (Section 3)
Ring: Circuit High or ”+” 7.8 Volt, Nominal
0 ohms, Nominal
Sleeve: Common

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5SYSTEM INITIALIZATION:
5.01 GENERAL:
The System 200 Signal Analyzer will INITIALIZE or REINITIALIZE upon:
1. Turning the power on with the POWER SWITCH.
An interruption of mains power (pulling the cord) will shut the analyzer down. After
reestablishing mains current, the POWER SWITCH must be pressed.
2. Inserting a connector into the front panelLINE LEVEL INPUT JACK or pulling this
connector out.
5.02 INITIALIZATION –THE dBm MODE:
The System 200 will INITIALIZE in the dBm MODE if a connector is inserted into the
front panelLINE LEVEL INPUT JACK.
INITIALIZATION parameters are as follows:
1. dBm MODE
2. BASE LINE LEVEL or Input Preamp Setting -30 dBm
3. BANDWIDTH –One-Third Octave Filters selected
4. DISPLAY MODES
A. REAL TIME MODE
B. AVERAGE MODE
5. SMOOTHKING TIME –Slow
6. MONITOR DISPLAY –Level
7. WEIGHTING –FLAT MODE
If a input signal is being fed to the System 200 Mainframe through its rear panel LINE
LEVEL INPUT CONNECTOR, a dummy plug must be inserted in the front panel LINE
LEVEL INPUT CONNECTOR so that the dBm MODE will be selected. Please refer to
Figure 3.02

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5.03 INITIALIZATION –THE dB/spl MODE:
The System200 will INITIALIZE in the dB/spl MODE if a connector IS NOT inserted
into the front panelLINE LEVEL INPUT JACK.
INITIALIZATION parameters are as follows:
1. dB/spl MODE
2. BASE LINE LEVEL or Input Preamp Setting 70 dB/spl
3. BANDWIDTH– One-Third Octave Filters selected
4. DISPLAY MODES
5. REAL TIME MODE
6. AVERAGE MODE
7. SMOOTHING TIME – SLOW
8. MONITOR DISPLAY – LEVEL
9. WEIGHTING – FLAT MODE

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6INPUT LEVELS:
6.01 CONTROL:
Both microphone and LINE LEVEL INPUT levels are adjusted in 10 dB steps by the ▲▼
KEYS located on the 12-KEY KEYBOABD.
The result of adjustment is the BASE LINE VALUE which is displayed on the POSITION
DISPLAY. The BASE LINE VALUE changes in 10 dB steps as the INPUT GAIN is
changed.
6.02 RANGE:
Line level inputs may be between...
-70 dBm and +40 dBm
BASE LINE VALUES are...
-70, -60, -50, -40, -30, -20, -10, 0 dBm
Microphone level inputs may be between...
30 dB/spl and 140 dB/spl
BASE LINE VALUES are...
30, 40, 50, 60, 70, 80, 90, 100 dB/spl
Figure 6.01

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6.03 DYNAMIC RANGE (Processing):
The System 200 Signal Analyzer processes a dynamic range window of 46.5 dB.
Therefore...
If the dBm BASE LINE VALUE is adjusted to -10 dBm, the processing dynamic range is
between -10 dBm and +36.5 dBm (-10 + 46.5 = 36.5).
Or...
If the dB/spl BASE LINlE VALUE is adjusted to 60 dB/spl, the processing dynamic range
is between 60 dB/spl and 106.5 dB/spl (60 + 46.5 = 106.5).
For sake of simplicity we will refer to the dynamic range processing window as 45 dB
from this point forward.
6.04 OVER RANGE CONDITION
If the input signal is greater than the sum of the BASE LINE VALUE plus 45 dB, an
OVER RANGE condition will exist. This is displayed on the MONITOR DISPLAYas…
OR
…or lights lit in the 0-R row of the FILTER DISPLAY and BROADBAND DISPLAY.
Adjust the INPUT DISPLAY ▼to achieve an appropriately higher BASE LINE VALUE.
6.05 INPUT PREAMP OVERLOAD:
A LED. PREAMP OVERLOAD INDICATOR is located just below the POWER SWITCH.
This light indicates a clipping condition in the input preamplifier.
Clipping of the input preamplifier will occur at approximately 50 dB above the BASE
LINE VALUE.
See Section 6.01 and 6.02
6.06 UNDER RANGE CONDITION:
If a signal equal to or less than the BASE LINE VALUE is input, an UNDER RANGE
condition will exist. This is displayed on the MONITOR DISPLAYas…
UR
…Adjust the INPUT GAIN KEY ▲to achieve an appropriately lower
BASE LINE VALUE.

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7PROCESSING MODES:
7.01 GENERAL:
The System 200 Signal Analyzer processes in bothAVERAGE and PEAK MODES
simultaneously. Therefore, the STORE IN MEMORY and ACCUMULATE IN MEMORY
functions as well as REAL TZME will be executed in bothAVERAGE and PEAK MODES
simultaneously.
The mode displayed is controlled by the AVERAGE/PEAK CHANGE KEY. The operation
of this key is transient free since the System 200 is processing in both modes
simultaneously.
Both the PEAK MODE and AVERAGE MODE may be simultaneously displayed.
Touch the SHIFT KEYlocated on the 12-KEY KEYBOARD.
Touch the PEAK/AVERAGE CHANGE KEY until both the PEAK and AVERAGE
INDICATORS are lit.
The analyzer will now toggle betweenPEAK, AVERAGE and PEAK/AVERAGE.
To exit this mode...
Touch the SHIFT KEY
Touch the PEAK/AVERAGE CHANGE KEY
7.02 AVERAGE MODE:
The AVERAGE MODE employs circuitry which smoothes or averages the signal
according to one of the three time constants selected by the SHOOTHING TIME
CHANGE KEY. See Section 8.
This smoothing, optimized for each frequency, provides a statistical probability of the
signal’s amplitude being ±a given number of dB from a light on the analyzer a given
percentage of the time. The smoothing also provides a steady display, which may be
easily read.

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7.03 PEAK MODE:
The REAL TIME display in the PEAE MODE shows an almost instantaneous rise of the
signal followed by a slow decay similar to many Peak Program Meters. The intended
application of the PEAK MODE is program monitoring as opposed to acoustic analysis
using PINK NOISE.
The signal’s peaks or maximums are almost instantly stored by a capacitor in the
circuitry. The capacitor’s charge is slowly bled-off through a resistor to ground. The
circuit, once charged, is immune to subsequent signal peaks unless they are greater than
the capacitor’s charge.
The decay or rate at which the capacitor’s charge is bled-off may be selected with the
SMOOTHZNG TIME CHANGE KEY. Selecting SLOW will result in a long decay which
might be appropriate for monitoring Peak Program material. Selecting FAST will result in
a very rapid decay.

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9FILTERS AND BANDWIDTH:
9.01 GENERAL:
The System200 Mainframe will accommodate a total of 13 Filter cards. These cards
carry the ONE-THIRD OCTAVE, ONE-SIXTH OCTAVE, OCTAVE BAND, or custom
filters currently available.
The filter cards are coded with jumpers to tell the analyzer which filters they are. As a
result, the cards need not be installed in any particular order as long as they are installed
in the slots designated for filters. (See Drawing #B 101356 –Appendix).
Filter card slots 1 through 8 are powered separately from slots 9 through 13. It is
therefore good practice to use the slots which allow a full set of filters to be powered
from one power source (i.e. the switchable one-third octave/octave band, three-pole filter
set, 200-01-00).
Presently the analyzer’s software recognizes three filter sets as follows:
l. 30 (1/3 OCTAVE FILTERS)
2. 30 1/6 OCTAVE FILTERS
3. 10OCTAVE BAND FILTERS
A maximum of 30 filters may be displayed on the FILTER DISPLAY at any one time.
The 1/3 OCTAVE and the 1/6 OCTAVE FILTERS are processing input data continuously
when the analyzer is on. Thus, there is no settling time when switching the FILTER
DISPLAY between them.
When the OCTAVE BAND FILTERS are selected, the program takes the 1/3 OCTAVE
FILTERS apart and uses some of their components to form the OCTAVE BAND
FILTERS. As a result, the user must allow for settling when selecting in and out of the
OCTAVE BAND FILTER SET.

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9.02 200-01-00 OPTION: ONE-THIRD OCTAVE/OCTAVE BAND, THREE-POLE FILTER
SET: 200-01-00OPTIONCHART
30 Three-Pole, One-Third Octave Filters (25 Hz thru 20 kHz, on I.S.O. centers)
SWITCHABLE TO –
10 Three-Pole, Octave Band Filters (31.5 Hz thru 16 kHz, on I.S.O. centers)
This is a set of 8 filter cards carrying 30 One-Third Octave, Three-Pole Filters from 25 Hz
through 20 kHz on I.S.O. centers. In addition, there are 10 Octave Band, Three-Pole Filters
on I.S.O. centers from 31.5 Hz through 16 kHz. The Octave Band Filters share some circuitry
with the One-Third Octave Filters.
These filter cards are coded to respond when the 1/3 or OCTAVE
BANDWIDTH MODE is selected. They are factory installed in filter card slots 1 through 8.
It should never be necessary to change the jumper pattern for this set of filters. (See Section
9.07). See the above 200-01-00 Option Chart.