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Agilent Technologies. We have made no changes to this manual copy. The HP XXXX referred to in this document is now the Agilent XXXX. For example, model number HP8648A is now model number Agilent 8648A.
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SPECIFICATIONS 0.008 to 1200 cps in five decade ranges with wide overlap a t each FREQUENCY RANGE: dial extreme. ". Within *2% f r o m "1. 2" to "121q on dial; *3% f r o m 8" to "1.2". DIAL ACCURACY: Within including warm-up drift and line voltage variations of...
CONTENTS SECTION I GENERAL DESCRIPTION Page ... General 1 - 1 SECTION II OPERATING INSTRUCTIONS ..Inspection Controls and Terminals ..230-Volt Operation .
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GENERAL plitude device so that no A. V. C. system, with as- sociated delay in stabilization after frequency changes, The Model 202A Low Frequency Function Generator is required a compact, convenient, and versatile source of transient-free test voltages between 1200 and .008 The frequency range from .008 to 1200 cycles per...
Sect. I1 Page 1 SECTION II OPERATING INSTRUCTIONS INSPECTION OUTPUT This group consists of three terminals. The one marked "G" is connected directly to the instrument After the instrument unpacked, the instrument chassis. The other two terminals, vertically aligned, should be carefully inspected for damage received a r e the OUTPUT terminals.
Under circumstances where the connection places sured any convenient frequency and the output the Model 202A in series with a path carrying cur- level will be correct (within these limits) for any rent, distortion of the Model 202A output will occur other frequency.
Figure 3-1 depicts the general scheme of the @Model produce an accurate integral of the applied square 202A and indicates the waveforms produced. The bi- wave. The bi-stable circuit and linear integrator stable circuit consists of a flip-flop circuit capable...
Sect. III Page 2 The portion of the diagram composed of V1, V2 non-linear system which synthesizes a sinewave and V3 i s the "bi-stable circuit". Actually, this from the triangular wave. This network consists circuit is a combination of two circuits. capa- of a group of biased diodes arranged in such a man- citors C10 and C13 a r e disconnected so that there...
Sect. III Page 3 reference. When V3B conducts the Bi-Stable Unit virtually no signal at the junction of R and C the is flipped back to its original state, completing one output voltage must also be triangular. cycle of operation. In this case the frequency of the applied signal Voltage regulator tubes V5 and V6 a r e connected low that the amplifier used must be direct coupled.
Sect. Page Figure 3-4. Simplified Linear Integrator SINE SYNTHESIZER A N D F U N C T I O N the average level of the output can be adjusted to SELECT O R S W I T C H exactly the voltage midway between the "reference" levels.
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Sect. Page 5 1 1 1 E l - S T A B L E 2 2 5 VDCREG I D . I . 6 M O U T P U T REG. A M P L I F I E R Figure 3-5.
R94 and R95 is a simple linear divider The signals appearing a t the plates of V19 a r e for all voltage levels. It is adjusted to give equal Figure 3-7. Output Amplifier System of Model 202A...
C29. In all other description the reference level a t the plate of multiar diode V3, one positive pulse for operation has been B-, and in the Model 202A and one negative pulse appear for every cycle of the B- line is completely isolated from the chassis.
Sect. 1 1 1 Page 8 of the sync pulse amplifier, V17, through an RC POWER SUPPLY coupling which lowers the average voltage on the grid to B-. In the absence of pulses, V17 is biased The Power Supply is a full wave rectifier and regula- to cut-off by the bleeder to B+.
Defective OA2 tube Instrument inoperative Interaction between most of the circuits of the Model (normal 37W reg- 202A makes a fairly definite procedure for trouble (V5). ulated) (+225V reg- shooting necessary. F o r example, a fault in the ulated, off voltage).
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Sect. Page 2 TABLE 4-2. (CONT'D) F U N C T I O N G E N E R A T O R (bi-stable circuit and integrator) CAUSE AND/OR REMEDY SYMPTOM REPAIR ANALYSIS OF FUNCTION GE3lERATOR Same symptoms a s Try replacement voltage, then a simple test should be made to deter- tubes for V15, V16,...
See para- No sync pulse (Check Replace Vl7. for negative pulse graph 4-9. with oscilloscope and See paragraph 4-4. with Mode1 202A set DC voltage component for highest frequency). exists across the OUT- PUT terminals. Large overshoot. Replace CR1.
225 regulated voltages. "Power Supply Regulator Adjustment". Paragraph 4-9. 2) Connect the 202A the power line and turn on. P O W E R SUPPLY REGULATOR The voltmeter indication should be between ADJUSTMENT 230 volts with line voltage s e t to 115 volts.
202A that a r e not a t ground potential. A Distortion by R54. The signal impedance of this point is very Analyzer and an Oscilloscope will also be required.
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5 volts when R93B. This is the AMPLITUDE control is rotated through full green wire connected to the AM- PLITUDE control. range. -hp- -hp- -hp- MODEL 2 0 2 A MODEL 3 3 0 MODEL 120 OR 130 LOW FREQUENCY...
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Sect. Page 7 (A) Correct setting of reference levels. (B) Both Ref. levels too large. (C) +Ref. too high and -Ref. too low. Frequency correct but large 2nd harmonic a s seen by peak flattening on one side and sharpening on other. Also sine average not same a s triangle.
The dial stops and not the potentiometer me- chanical stops should be limiting dial travel. Turn the 202A on, set the line voltage to 115 volts, turn the FUNCTION switch to "SQUARE", and allow a t least a 1 hour warm-up period.
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Sect. Page 9 4-14 REPLACEMENT O F R 5 8 Use only deposited carbon film resistors for R24, R25, R27, and R28 a s previously described for R26. POTENTIOMETER Again common type composition resistors can be Replacement of the frequency control potentiometer used for series pads provided they do not exceed 10% involves two basic operations: of the total resistance value.
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COUPLER A C C E S S Figure 4-4. Model 202A Top View Cover Removed...
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Figure 4-6. Model 202A Function Generator and Amplifier...
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BLACK NOTES: (APPLY TO FUNCTION GENERATOR 8 AMPLIFIER SECTION AS WELL AS TO POWER SUPPLY SECTION). CONDITIONS OF DC VOLTAGE MEASUREMENT: 1000 OHMS PRI. I I MEGOHM 1 . 115/230V. 5 0 / 1 0 0 0 ' L POWER SUPPLY MAIN (EXTERNAL) CHASSIS,ISOLATED FROM POWER SUPPLY WHITE 2.
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Sect. V Page 1 SECTION V TABLE OF REPLACEABLE PARTS N O T E A n y c h a n g e s i n t h e T a b l e of R e p l a c e a b l e P a r t s w i l l b e l i s t e d o n a P r o d u c t i o n C h a n g e s h e e t a t t h e f r o n t of t h i s m a n u a l .
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Page Sect. T A B L E O F R E P L A C E A B L E P A R T S Total quantity used in instrument.
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Sect. V Page 3 T A B L E O F R E P L A C E A B L E P A R T S Total quantity used in the instrument.
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Page Sect. T A B L E O F R E P L A C E A B L E P A R T S # Total quantity used in the instrument.
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Page 5 Sect. T A B L E O F R E P L A C E A B L E P A R T S...
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Page Sect. T A B L E O F R E P L A C E A B L E P A R T S Total quantity used in the instrument.
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Sect. Page T A B L E O F R E P L A C E A B L E P A R T S...
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Sect. V Page 8 T A B L E O F R E P L A C E A B L E P A R T S STOCK CIRCUIT DESCRIPTION, MFR. & MFR. DESIGNATION REF. This circuit reference not assigned R84a-f, 20%-26C Resistor: fixed, wirewound...
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V Page Sect. T A B L E O F R E P L A C E A B L E P A R T S...
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Sect. V Page T A B L E O F R E P L A C E A B L E P A R T S Total quantity used in the instrument.
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LIST OF CODE LETTERS USED I N TABLE O F REPLACEABLE PARTS TO DESIGNATE THE MANUFACTURERS CODE CODE L E R MANUFACTURER ADDRESS LETTER MANUFACTURER ADDRESS Aerovox Corp. New Bedford, Mass. Hammerlund Mfg. Co., Inc. New York N. Y. Industrial Condenser Corp. Allen-Bradley Co.
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CLAIM FOR DAMAGE IN SHIPMENT The instrument should be tested as soon as it is received. If it fails to operate properly, or is damaged in any way, a claim should be filed with the carrier. A full report of the damage should be obtained by the claim agent, and this report should be forwarded to us.
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S e r i a l 6411 and above; a l s o S e r i a l s 6065, 6211, 6218, 6234, 6238, 6369, 6375, 6384, 6388, 6392 and 6404: Change t o range s w i t c h assembly; -hp- Stock No, 202A-l9C, Mfr,, HP...
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67539 67549 67559 67579 6758: 67529 6756, C1,2: Change to capacitor, fixed, electrolytic, 20uf, vdcw; -hp- Stock No, 18-20HP, Mfr., CC Add capacitor, fixed, electrolytic, 2 sections, 20uf/sect, vdcw; -hp- Stock No, 18-22HP, Mfr,, CC R120 thru Add resistor, fixed, composition, 150,000 ohms...