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4-35

4.10 SPECTRUM ANALYZER MODE

The spectrum analyzer display provides a view of the system spec-
trum with variable spans from 50 MHz to 3 MHz and a dynamic
range of better than 60 dB. When the

Spectrum

key is pressed, the

following screen is displayed.

Содержание 3SR

Страница 1: ...4607 E Mail catvsupport wavetek com Internet http www wavetek com 9 97Rev J Manual Part No 6510 00 0272 This document contains information proprietary to Wavetek The information in this document is n...

Страница 2: ...used by improper storage improperinstallation unauthorizedmodification misuse neglect inadequatemaintenance accidentorforanyProductwhichhasbeenrepairedoralteredbyanyoneotherthanWavetek or its authoriz...

Страница 3: ...2 7 Telemetry 1 4 1 2 8 Spectrum Mode 1 4 1 2 9 Intermodulation Distortion 1 5 1 2 10 Depth of Modulation 1 5 1 2 11 Printer Interface 1 6 1 2 12 General 1 6 1 2 13 Powering 1 6 1 2 14 Standard Access...

Страница 4: ...ing 3 5 SECTION 4 OPERATION HOW TO USE THE 3SR RECEIVER 4 1 INTRODUCTION 4 1 4 2 STEALTH START UP PROCEDURE 4 1 4 3 SETUP 4 3 4 3 1 General Setup 4 4 4 3 2 Measurement Setup 4 8 4 3 3 How To Setup You...

Страница 5: ...nting Auto Test Files 4 59 4 14 STATUS 4 66 SECTION 5 REVERSE SWEEP OPTION 5 1 INTRODUCTION 5 1 5 1 1 Wavetek Stealth Reverse Sweep Concept 5 1 5 1 2 Basic Reverse Sweep Procedure 5 2 5 1 3 Interfacin...

Страница 6: ...ERATION 5 18 5 7 1 Sweep Direction Indicator 5 18 5 7 2 Changing the Sweep Direction 5 19 5 7 3 Reverse Noise Feature 5 19 5 7 4 Telemetry Level Indicator 5 19 5 7 5 Forward and Reverse Sweep Referenc...

Страница 7: ...he receiver to maintain the utmost measurement accuracy With the Reverse Sweep option a transmitter is built into the hand held sweep receiver The headend sweep transmitter 3ST is set up to receive th...

Страница 8: ...hensive set of information is provided tuned channel video frequency and level audio frequency and level the difference between video and audio carrier levels The 3SR Receiver is a streamlined hand he...

Страница 9: ...V input level Carrier to Noise Ratio Depth of Measurement Characteristics Video Carrier Level dBmV Carrier to Noise Range 0 10 20 30 40 50 60 10 0 10 14 24 Typical C N specifications for a noise measu...

Страница 10: ...ge At least 16 including Forward Reverse or Sweepless Sweep Trace Storage At least 50 including Forward Reverse or Sweepless Reverse Option Transmitter Output 10 to 40 dBmV settable in 2 dB increments...

Страница 11: ...n 6 vertical divisions Spurious Free Dynamic Range 60 dB typical specifications 1 2 9 Intermodulation Distortion CSO CTB Characteristics Video Signal Level dBmV Depth of Measurement dB without preampl...

Страница 12: ...25 C 20 dBmV Dimensions 15 2 cm W x 25 4 cm H x 5 1 cm D 6 W x 10 H x 2 D Weight 1 95 kg 4 3 lbs w Reverse Sweep Option 2 2 kg 4 9 lbs Operating Temperature Range 20 to 50 C 0 to 122 F w Reverse Sweep...

Страница 13: ...inter 3010 59 0009 Citizen PN60 Printer Ribbons 2 included with printer 1217 50 0159 Citizen PN60 Printer Cable included with printer 1019 00 0437 Charger Adapter 220VAC to 18 VDC SBC 1 Charger for on...

Страница 14: ...Preselector 125 to 250 MHz 7204 Tunable Precision Preselector 250 to 500 MHz 1 Specification Change The transmitter output is being changed from 10 to 40 dBmV to 20 to 50 dBmV To determine which tran...

Страница 15: ...phone Wavetek immediately Save the shipping carton and packing materials for possible future use FOR CUSTOMER SERVICE call WAVETEK 800 851 1198 International Customers contact your local Wavetek Repr...

Страница 16: ...tter and a Serial Printer cable The following information describes each of the associated cables Stealth to Stealth The Stealth to Stealth cable 1217 50 0149 provided with each 3ST Transmitter is use...

Страница 17: ...2 3 Serial Printer Cable The Serial Printer Cable 1217 50 0151 can be used to print data directly from the 3SR Receiver Tx Rx GND DTR Rx Tx DTR GND DSR CTS...

Страница 18: ...e in any way phone Wavetek immediately Save the shipping carton and packing material in the event that you have to return it FOR CUSTOMER SERVICE call WAVETEK 800 851 1198 International Customers cont...

Страница 19: ...keypad includes eight Soft keys eight Measurement Mode selection keys three Support Mode selection keys four Arrow keys sixteen Numeric Entry keys Power key 3 2 1 Soft Keys There are a total of eight...

Страница 20: ...below the display LEVEL Signal level measurements on individual channels are made by entering a specific channel number and pressing the channel key Measurements can also be made by selecting the carr...

Страница 21: ...tuned channel in either or dB as selected by the operator MOD Allows the user to listen to the modulation of the tuned channel or frequency and measure Depth of Modulation of a video carrier SPECT Pr...

Страница 22: ...ach operating mode These keys are located below the Measurement Mode Selection keys and to the right of the Support Mode Selection keys 3 2 5 Alpha Numeric Entry Keys The Alpha Numeric keys are used t...

Страница 23: ...minated by pressing the ENTER key Numeric Entry Mode In the numeric entry mode only the numerals 0 through 9 and the decimal point can be entered When negative values are allowed the FCN key sequence...

Страница 24: ...the broad caster The following procedure describes the steps to prepare the receiver for use Building A Channel Plan 1 To build a channel plan first enter the setup mode by pressing the SETUP key 2 P...

Страница 25: ...your MAX MIN to fluctuate You can solve this problem two ways Either disable the enabled channel in edit channel parameters Or make an active channel outside of the bandwidth you are wanting to test B...

Страница 26: ...hannel to ensure that it is designated appropriately A special algorithm is used to ensure that the peak of these signals is measured At this time you may also wish to designate tilt channels and labe...

Страница 27: ...e the Up and Down soft keys to scroll to additional setup items When lists are being displayed the up arrow soft key dims when the first item in the list is reached and the down arrow soft key dims up...

Страница 28: ...in or always on The unit can be manually turned off at any time by pressing the Power key Use the UP and DOWN arrow keys to set the time out period Backlight Time out Period An additional means of con...

Страница 29: ...data bits 1 stop bit no parity flow control hardware handshaking A serial to parallel converter such as the one manufactured by Black Box Corp is required for printing to a parallel printer The setup...

Страница 30: ...set all parameters to the factory default values Warning All files and references will be lost when resetting the unit to factory default settings Display Test Allows the user to test the operation o...

Страница 31: ...to a local carrier frequency Sweep Telemetry On Off When turned on will modulate the CW signal similar to the telemetry signal 4 3 2 Measurements Setup Temperature Unit Use the UP and DOWN arrow keys...

Страница 32: ...e fundamental hum frequency to be measured can be selected using the UP and DOWN arrow keys 60 Hz 50 Hz Auto When Auto is selected the unit will automatically switch to 50 Hz on PAL type plans and 60...

Страница 33: ...light the selection and press the ENTER key The unit will provide a prompt to ensure that no cable is connected to the RF input Once verified press the OK soft key to perform the calibration The unit...

Страница 34: ...e deletion of the channel plan The currently active channel plan as indicated in the lower right hand corner of the screen cannot be deleted To delete this plan first select a different plan by using...

Страница 35: ...when completed Step 3 Enter the frequency at which to stop searching for channels Press the ENTER key followed by the OK soft key to set the stop frequency The 3SR Receiver will sequence through all...

Страница 36: ...select the channel that you wish to edit Press the Edit soft key to view and edit the following parameters Note If the parameter that you wish to edit does not appear on the screen keep pressing the...

Страница 37: ...rement modes An RMS detection mode is used when measuring the level of a digital channel Frequency The frequency of the carrier for TV and DUAL types this is the frequency of the video carrier Enter f...

Страница 38: ...se level is measured is the Carrier frequency plus the noise offset To adjust the noise offset cursor to the Noise Offset selection The offset can be adjusted by using the UP and DOWN arrow keys or by...

Страница 39: ...elete Unused Channels Once the channel plan has been built unused channels can be deleted if desired Doing this frees memory for other uses and unclutters the channel plan Select the Delete Unused Cha...

Страница 40: ...ype carrier also Use the All None soft key to quickly select or deselect Auto Test measurements If a test is selected the None soft key is displayed If no tests are selected for a particular channel t...

Страница 41: ...the limits for FCC specified values Copy Remote Plan This selection allows you to copy a channel plan from one unit to another Connect a cable between the serial ports of two units Ensure that the ba...

Страница 42: ...s to the n 10 x flatness formula The x in the equation is the sweep limit variable This value is adjustable from 0 0 to 5 0 default 1 0 Use the UP and DOWN arrow keys or the numeric entry keys to ente...

Страница 43: ...P and DOWN arrow keys or the numeric keypad to enter the forward telemetry frequency corresponding to the 3HRV NOTE For successful operation the 3SRV telemetry frequency must match the forward telemet...

Страница 44: ...Reverse Telemetry Level take into consideration the following losses system summing network test point and amplifier desired input NOTE The frequency of the reverse telemetry carrier is set on the 3S...

Страница 45: ...p file Use the UP and DOWN arrow keys to enable the option Include Audio Carriers Sweepless Mode Only This selection allows the audio carriers to be excluded resulting in a faster sweep Use the UP and...

Страница 46: ...number or frequency Channel label Video carrier frequency and level numerical Audio carrier frequency and level numerical Analog meter of carrier levels Delta between audio and video levels Selected c...

Страница 47: ...y use the numeric keys to enter a frequency followed by the FREQ key The frequency can then be decremented by using the left key or incremented using the right arrow keys The step size when tuning by...

Страница 48: ...be compensated with an adjustment but repaired instead To balance the amplifier ensure that the AGC and ASC is switched off Tilt mode simplifies the actual balancing by displaying a bar graph with a...

Страница 49: ...To adjust the Scale use the UP and DOWN arrow keys to select a scale that will provide the best viewing of the Tilt levels To adjust the Ref Level press the Ref Level soft key Now the Ref Level can be...

Страница 50: ...ls Selected channel plan Battery status Test point compensation appears only if a nonzero value is programmed during setup When the SCAN key is pressed a graph showing all carrier levels is displayed...

Страница 51: ...the Scan display Use the UP and DOWN arrow keys or the numeric entry keypad to set the start frequency Press the Stop soft key to adjust the stop frequency The Full Span soft key can be used to set t...

Страница 52: ...sulting in a faster scan This feature is selected in the Measurement Setup menu An indicator appears in the upper left hand corner of the Scan screen when audio carriers are omitted Limits The Limits...

Страница 53: ...n turned off the limit annunciators do not appear 4 7 HOW TO MEASURE C N It is a good engineering practice to use a bandpass filter on the input of the receiver when making C N measurements This is to...

Страница 54: ...nd then tuning to the offset frequency searches for a quiet line Once a quiet line is found the unit will then measure four consecutive frames and average the values together The value is then correct...

Страница 55: ...values can also be defined individually for each channel in the Channel Plan setup menu Note BW and Noise Offset values can be defined individually for each channel see section 4 3 4 How To Edit Chann...

Страница 56: ...ly in the amplifier possibly a capacitor going bad and aggravating the ripple A proprietary DSP technique enables Hum measurements on modulated carriers non scrambled channels Information displayed in...

Страница 57: ...TION This function allows you to monitor the video depth of modulation in graphical and precise numerical format A marker is placed at the optimal modulation level NTSC 87 5 PAL 90 to assist techni ci...

Страница 58: ...R MODE The spectrum analyzer display provides a view of the system spec trum with variable spans from 50 MHz to 3 MHz and a dynamic range of better than 60 dB When the Spectrum key is pressed the foll...

Страница 59: ...e adjusted using the cursor keys or by entering a numeric value followed by the enter key The scale parameter 1 2 5 10 dB Div can only be adjusted with the cursor keys For example if the reference lev...

Страница 60: ...d reads the delta indicated at the bottom of the screen The FCC requirement is a window of 2 0 dB which means the delta should be 4 dB How To Make CSO CTB Measurements CSO Composite Second Order is a...

Страница 61: ...4 38 Press the OK soft key once the carrier has been turned off The CSO CTB measurement is now displayed...

Страница 62: ...oducts The measurement value is computed by a ratio of the peak level of the video carrier to the peak of the distortion products of the second and third order beats The worst case CSO value is highli...

Страница 63: ...n The Sweep function has two operating modes Stealth or Sweepless The current sweep mode is indicated in the upper right hand corner of the screen The Stealth mode allows sweep insertion points to be...

Страница 64: ...or a specific value can be entered using the numeric keys followed by the ENTER key A sub function under the Frequency soft key is Marker Zoom This will change the start and stop frequency to coincide...

Страница 65: ...tical markers are adjusted using the top two sets of soft keys correspond ing to the displayed arrows The horizontal markers are turned on and off in the Sweep setup screen The horizontal markers are...

Страница 66: ...works using the reference comparison method commonly called normalization With this method the response at the test point is compared to a reference that was stored at the first amplifier or fiber nod...

Страница 67: ...Measurement Files The Store Measurement feature allows the user to store sweep spectrum and scan measurements To store a measurement press the File key while taking the measurement Press the Store Me...

Страница 68: ...be printed using the Print soft key All measurement files with the exception of scan files can be printed using the Print All soft key Use the Delete soft key to delete all unwanted files There are se...

Страница 69: ...e press the File key followed by the Sweep References soft key Next press the Store soft key to name and store the sweep measurement as a reference NOTE The Store soft key is only active if Sweep was...

Страница 70: ...sweep The sweep file is selected from the Measurement Files screen the same as if it were to be viewed The Sweep screens appears upon pressing the View soft key When the Sweep File Overlay option has...

Страница 71: ...rently selected reference are shown beneath the marker information The level and frequency adjustments affect both the stored and live sweeps The reference limits checking and tilt compensation are ap...

Страница 72: ...Test report The Test Locations can be created directly on the Stealth unit or using the SteathWare Data Analysis software and downloaded to the Stealth unit The Test Location is used to identify where...

Страница 73: ...4 50 Press the New soft key to create a new Test Location file The unit will then prompt for a file name Once a name is entered press the OK soft key to execute the operation...

Страница 74: ...ker Config 1 9 1 5 Trunk Termination NO YES NO 6 Voltage Setting LOW MID HIGH 7 Rev Pad 100 0 100 0 0 0 dB 8 Rev Equalizer 100 0 100 0 0 0 dB 9 Fwd Pad 100 0 100 0 0 0 dB 10 Fwd Equalizer 100 0 100 0...

Страница 75: ...ameters have been edited press the OK soft key The Delete soft key is used to delete a specific location file 4 13 2 How To Perform An Auto Test The Auto Test mode provides automated FCC 24 hour testi...

Страница 76: ...ocation Using the Up and Down arrow keys select an Auto Test location Select NONE if location information is not desired Press the OK soft key when completed To create a new Auto Test location press t...

Страница 77: ...d Press the ENTER key after each parameter is entered to update the display If changes are made and you want them updated in the location file press the Save soft key If changes are made and the Save...

Страница 78: ...Point type When the desired Test Point type is selected press the OK soft key The following is a list of Test Point types available Trunk Amp Forward Trunk In Forward Trunk Out Bridger Reverse Trunk...

Страница 79: ...e the numeric entry keys to enter the following system voltage measurements AC Voltage DC Voltage regulated DC Voltage unregulated The voltage measurement are printed in the Auto Test report Press the...

Страница 80: ...is used to account for loses associated with certain amplifiers Use the UP and DOWN arrow keys or the numeric entry keys to enter the Test Point Compensation 100 0 to 100 0 dB in 0 1 dB steps Press th...

Страница 81: ...mence the Auto Test Press the Scheduled soft key to perform the Auto Test repeatedly at scheduled intervals Immediate If the Immediate mode is selected the unit will commence the Auto Test sequence Pr...

Страница 82: ...gress the measurement currently being performed i e Level C N Hum or Modulation is indicated on the screen A bar graph showing the percentage of completion is dis played Scheduled If the Scheduled mod...

Страница 83: ...mence the Schedule Auto Test If the first interval is to commence immediately the unit will prompt you to enter the ambient temperature The temperature displayed is the temperature sensed by the unit...

Страница 84: ...ompletion of the Auto Test the unit will enter the Auto Test Results Mode to display the Auto Test files This allows the user to view or print the Auto Test results Use the Up and Down arrow soft keys...

Страница 85: ...isplayed If the Auto Test was performed immediately then only one interval is displayed If the Auto Test was performed using scheduled intervals then all the interval numbers are displayed The Print A...

Страница 86: ...lure of the measurements taken during that interval A check mark indicates that all measurements were within the specified limits To comply with FCC 24 hour testing requirements the 24hr Report soft k...

Страница 87: ...0 05 00 00 11 00 00 Temp 75 F 61 F 59 F 83 F Video Video Video Video 24 Hr Chan Level Level Level Level Deviation dBmV dBmV dBmV dBmV dB 2 9 6 8 8 17 7 LO 10 7 28 4 HI 3 9 9 8 6 5 8 LO 8 9 15 7 HI 4 9...

Страница 88: ...direction that the measurement was out of specifica tion Each interval can be selected and viewed as desired Use the Up and Down arrow soft keys followed by the View soft key to view specific interval...

Страница 89: ...ents C N Hum and Modulation measurements When viewing the list of C N Hum and Modulation measurements the following symbols will replace the measurement value if an error occurred UNDER under range OV...

Страница 90: ...3 TNN 5 8 LO 13 9 8 1 4 USA 2 9 LO 15 6 12 7 0 9 5 ESPN 0 1 16 1 16 2 48 2 6 MTV 7 9 20 3 28 2 HI 88 2 7 FMLY 9 9 10 6 20 5 HI 8 CMDY 6 9 11 5 18 4 HI 12 7 9 LIFE 9 1 11 1 20 2 HI 10 VH1 8 5 13 3 21...

Страница 91: ...if unwanted files should to be deleted to make more memory available for newer files 1 Specification Change The transmitter output is being changed from 10 to 40 dBmV to 20 to 50 dBmV To determine wh...

Страница 92: ...4 69...

Страница 93: ...on where channels exist and where sweep signals are inserted For forward sweeping the channel plan is built through a process in which the 3ST transmitter tunes through a standard or HRC or IRC channe...

Страница 94: ...oubleshooting 3HRV only The 3HRV provides feedback to the field as to the current condition of noise and ingress in the headend Even if the noise or ingress is swamping the telemetry a picture of the...

Страница 95: ...tures Single Cable Split Band Network The Model 3ST Sweep Transmitter or Model 3HRV Headend Reverse Sweep Receiver is connected in the headend as shown in figure 1 The connections are similar to those...

Страница 96: ...ion loss The connection at the node may be as shown in figure 4 Notice that in this configuration the forward and reverse test points are separated and two directional couplers must be used In all of...

Страница 97: ...e Network Another possible though rare network configuration is the Dual Cable Network in which a full bandwidth is used for both forward and reverse essentially two cable systems overlaying each othe...

Страница 98: ...vices are known the reverse channel plan can be built with a 250 kHz resolution Then the active service frequencies can be quickly edited out Alternatively if there is any uncertainty about the freque...

Страница 99: ...2 5 27 5 29 30 5 31 32 5 33 36 36 5 38 40 and 41 42 5 The best way to set up the Stealth reverse sweep channel plan is to build a plan with 250 kHz sweep insertion points from 5 to 45 MHz and then del...

Страница 100: ...ation The active component reverse laser or reverse amplifier typically specifies the optimum input level for the device in terms of an analog video carrier level measured with a 300 kHz resolution ba...

Страница 101: ...um reverse sweep output level is to observe the reverse spectrum at the headend reverse sweep receiver Model 3ST or 3HRV The spectrum should be max held for an extended period one half hour or more th...

Страница 102: ...mond key so ON appears in Edit box 5 Highlight Transmitter Attenuator 0 dB corresponds to maximum output level 50 dBmV on newer 3SR 6 Determine the output level by subtracting the attenuator setting f...

Страница 103: ...e UP and DOWN arrow keys or the numeric keypad to enter the forward telemetry frequency corresponding to the 3HRV NOTE For successful operation the 3SRV telemetry frequency must match the forward tele...

Страница 104: ...erse Telemetry Level to an appropriate value When adjusting the Reverse Telemetry Level take into consideration the following losses system summing network test point and amplifier desired input NOTE...

Страница 105: ...ping In the Sweep mode the 3ST should never see video or carrier levels above 12 dBmV on its input The forward sweep points being inserted into the system by the 3ST should be 14 to 16 dB below the vi...

Страница 106: ...ry and sweep points and the video carriers of the system When sweeping reverse using only the 3ST in the headend the level of the telemetry the telemetry coming back from the 3SRV needs to hit the inp...

Страница 107: ...need to be remembered The 3HRV has its own telemetry signal This must be set at a different frequency from that of the forward telemetry signal in the 3ST if both units are being used Both telemetry f...

Страница 108: ...ed by inserting the signal from the 3HRV into your system using the same method and level settings as for the 3ST In figure below DC A and DC C have the same value as also the forward telemetry levels...

Страница 109: ...th ingress spectrum as seen at the headend by simply pressing the Ingress soft key If the reverse telemetry is not received by the headend unit Model 3ST or 3HRV the operator will be given the option...

Страница 110: ...RV Up to 10 technicians can sweep the reverse path simultaneously 5 7 1 Sweep Direction Indicator The sweep direction is indicated in the upper right hand corner of the Sweep screen The letters FWD re...

Страница 111: ...sweep procedure The other requirement is that a proper carrier to noise and carrier to ingress ratio be maintained The Reverse Noise feature enables a quick swept noise test at the reverse sweep poin...

Страница 112: ...rence selected does not match the type of sweep being per formed The reference will then default to None IMPORTANT To use a reference its type must match the type of sweep currently being performed Wh...

Страница 113: ...Reverse Sweep option by looking at the status screen NOTE To view the status screen without turning the unit off and on press FCN CHN to select the Status screen The status screen below is from a 3SR...

Страница 114: ...nter conductor and penetrates the copper the screw will make contact with the aluminum The result can be a dissimilar metals interface depending on the composition of the seizing screw that may create...

Страница 115: ...someone notices a minor amount of hum in the picture of a customer two blocks away error rates start going up on a data modem or DMX box Somewhere in the area you find a connector cracked at the hous...

Страница 116: ...surement technique is similar to using a band pass filter for intermodulation tests composite second third order The objective is to avoid bombarding the RF input of the instrument with a large number...

Страница 117: ...hich the intermod products appear are not included Unfortunately this eliminates the ability to monitor the headend for CPD from a field test point Alternatively a Stealth Model 3HRV can be used This...

Страница 118: ...the Stealth 3SR The following is a list of all status indicators icons and an explanation of each The status indicators are displayed in the title bar as shown in the example below Video Carrier Audio...

Страница 119: ...ry frequencies are matched Message SORRY The selected reference cannot be used Condition The channel plan has been changed or a different channel plan has been selected since storing the reference Res...

Страница 120: ...dy exists Overwrite Condition A reference with the same name currently exists Response Overwrite the existing reference or choose another name Message SORRY This is an invalid name Please try again Co...

Страница 121: ...error has occurred Condition A system error has been detected Response Restart the unit and try again Message ERROR There is no response from the printer Condition The printer is not responding to the...

Страница 122: ...re Response Delete the corrupted file and select another sweep file Message ERROR A system error has occurred Please select another mode Condition A system error has been detected Response Select anot...

Страница 123: ...exists Response Overwrite or choose another name Message SORRY This is the name of a fixed plan and cannot be used Condition An attempt was made to name a channel plan with the name of a fixed plan R...

Страница 124: ...store the new plan Condition Memory is currently at maximum capacity Response Delete unwanted files to make more memory available Message WARNING There is not enough memory to save the changes Condit...

Страница 125: ...OR Hum cannot be measured on a scrambled channel Condition A channel that has been programmed as scrambled in setup has been selected in Hum mode Response Select a channel that is not scrambled Hum me...

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