MODEL 132 VCG/NOISE GENERATOR @ - 1981 - Wavetek THIS DOCUMENT CONTAINS INFORMATION PROPRIETARY TO WAVETEK AND IS SOLELY FOR INSTRUMENT OPERATION AND MAINTENANCE. THE INFORMATION IN THIS DOCUMENT MAY NOT BE DUPLICATED IN ANY MANNER WITHOUT THE PRIOR APPROVAL IN WRITING OF WAVETEK. SAN DIEGO 9045 Balboa Ave., San Diego, CA 92123 P. 0 Box 651, San Diego, Calif.
CONTENTS Section One SPECIFICATIONS Physical Section Two and Electrical Specifications . . . . . . . . . . . . . . OPERATION ...................... Inspection Operating Controls .................... ...................... Operation Section Three Description . . . . . . . . . . . . . . . . . . . . 11 MAINTENANCE Introduction ...................... Recommended Test Equipment ................ Checkout and Calibration .................. Troubleshooting .....................
SAFETY r via the facil ty i powe rwiring. Do not Thi s instrument i wire s dfor earth g ounding ith two wir extension e cords, plug adapter setc. bYPa ss earth grou dingn w BEFORE PLUGGING IN the instrument, comply with installation instructions. t sremoved. MAINT ENANCE may requir power e on w thi th einstrumen cover l e of the elect rica hl azards. shoul dbe don eonly by qualified personne awar WARNING notes call attention t operations.
1 SECTIO N SPECIFICATIONS VERSATILITY HORIZONTAL PRECISION Waveforms Sine YJ , square I-I , triangle 2/ waveforms and analog noise M.r , or digital noise l-u--L Dial Accuracy *2% of full scale, 1 Hz to 2 MHz Frequency Range of Signal 0.2 Hz to 2 MHz in 6 decade ranges Frequency Vernier One turn equals 1% of full scale. Ranges x 10 X l 00 X1K X10K XIOOK X1M 0.
Noise Cl o c k Frequency Switch selectable noise frequencies are listed Analog Noise Bandwidth Clock Frequency 10 Hz 100 Hz 1 kHz 10 kHz 100 kHz 160 Hz 1.6 kHz 16 kHz 160 kHz 1.6 MHz OPERATIONAL MODES FUNC Function Mode - Provides the selected form at the main output. S/N Signal-to-Noise operation adds noise to a selected signal of constant amplitude. The signal-to-noise ratio is variable from 0 to +60 dB. N/S Noise-to-Signal operation adds a selected signal to a constant amplitude noise.
SECTION l OPERATION 2. 3. INSPECTION The following procedures should be performed to assure the user that the instrument has arrived at its destination in satisfactory operating condition. Complete calibration and checkout instructions are provided in Section 4 to determine compliance with electrical specifications. 4. 5. 6. Checking Visually 7. After carefully unpacking the instrument, visually inspect the external parts for damage to knobs, dials, indicators, surface areas, etc.
20. 21. 22. 23. 24. 25. 26. 27. 28. Depress MODE - N/S push button and rotate S/N - N/S (dB) selector ccw through each position, checking for reduction in signal level. Verify that the S/N - N/S (dB) vernier attenuates the signal approximately 10 dB between each step of the S/N - N/S (dB) selector. OPERATING CONTROLS The operating controls and electrical connections for the Model 132 are shown in Figures 2-I and 2-2.
, 7 I WAVETEK ,, VCG!NQISE MO~EI.. 132 GENERATOR Figure 2-l. Operating Controls, Front Panel 10. 11. 12. FM - Depressing this push button along with the FUNC push button (7) allows the selected or z wave, to be signal, either /‘\u , vA , pseudo-randomly frequency modulated, or jittered. The modulating signal is provided by pseudo-random analog noise, and the S/N N/S (dB) controls frequency deviation.
amplitude remains constant, thus giving calibrated 0 to -50 d B signal-to-noise ratios. In the N/S mode, the signal is attenuated with the noise remaining unchanged, thus giving noiseto-signal ratios from 0 to -50 dB. The steps for this control are indicated in black numerals on the front panel. 14. 15. 16. 17. S/N - N/S (dB) Vernier - Allows a calibrated fine adjustment of the S/N - N/S (dB) step attenuator (13). This control is continuously variable over at least a 10 dB range.
SAN OILGQ l CALfFORNfA PAT. NO X268.738 OTHER PAT PEND. MAN fp1 tt.S,A. 115 VAC 114 AMP 23OVAC 7htAMP Figure 2-2. Operating Controls, Rear Panel OPERATION Operation as a Voltage Controiled Generator No preparation for operation is required beyond completion of the initial installation previously stated in this section.
6. b. For increasing frequency sweep with positive dc input, set dial to lower frequency limit. c. For decreasing frequency sweep with negative dc input, set dial to upper frequency limit. To sweep the audio range from 20 Hz to 20 kHz, set the controls to 20 Hz as follows: a. Set the main dial to 0.02. b. Set the frequency vernier to the full ccw position. c. Introduce a 0 to +5 V ramp into the VCG inputconnector. In example 1, the dial is set at 1.0 and 0 voltage is applied to the VCG input.
sired amplitude with OUTPUT VERNIER (dB) control. 4. 5. Operation as a Random FM Source Before using the generator as a random FM source, please note the following. The frequency of the generator is being varied or modulated by a changing voltage in the same way as described in “Operation as a Voltage Controlled Generator.” However, instead of using a dc ramp, or ac signal, a random analog voltage is used.
Converting to 230-Volt Line Power instruments are shipped from the factory with the power transformer connected for 1 15-volt line power, unless ordered for 230-volt use. Converting a 115-volt unit for 230-volt operation is a simple matter. 1. 10 Remove power cord. 2. 3. 4. Loosen two captive thumb screws on rear panel and remove panel. The conversion switch is located on the chassis. Use a thin-bladed screwdriver to move the 115230 switch to the 230 position.
SECTION 3 CIRCUIT DESCRIPTION GENERAL of the integrator is fed into the hysteresis switch. The hysteresis and output switches function like a Schmitt trigger with the limit points set at the waveform extremes, firing when the triangle wave reaches +1.25 volts and -1.25 volts. When firing occurs, the hysteresis and output switches are set, reversing the square wave fed into the integrator.
tion. The result is simultaneous generation of a square wave and triangle wave of the same frequency with the positive half cycle of the square wave coincident with the negative slope of the triangle wave. The magnitude of the capacitor across the integrator and amplitude of the current into the integrator determine the frequency of oscillation. Capacitance across the integrator is changed by rotating the frequency Hz selector.
