HP 3300A User manual

TM 11-6625-2495-14&P
TECHNICAL MANUAL
OPERATOR’S, ORGANIZATIONAL, DIRECT SUPPORT, AND
GENERAL SUPPORT MAINTENANCE MANUAL
(INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS)
FOR
GENERATOR, SIGNAL SG-747/U
(HEWLETT-PACKARD 3300A)
(NSN 6625-00-118-6736)
HEADQUARTERS, DEPARTMENT OF THE ARMY 4 AUGUST 1980

SAFETY STEPS TO FOLLOW IF SOMEONE IS THE VICTIM OF ELECTRICAL SHOCK
DO NOT TRY TO PULL OR GRAB THE INDIVIDUAL
IF POSSIBLE, TURN OFF THE ELECTRICAL POWER
IF YOU CANNOT TURN OFF THE ELECTRICAL POWER, PULL, PUSH, OR LIFT THE
PERSON TO SAFETY USING A DRY WOODEN POLE OR A DRY ROPE OR SOME OTHER
INSULATING MATERIAL
SEND FOR HELP AS SOON AS POSSIBLE
AFTER THE INJURED PERSON IS FREE OF CONTACT WITH THE SOURCE OF
ELECTRICAL SHOCK, MOVE THE PERSON A SHORT DISTANCE AWAY AND
IMMEDIATELY START ARTIFICIAL RESUSCITATION
5
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2
3
4
5

TM 11-6625-2495-14&P
WARNING
Adequate ventilation should be provided while using
TRICHLOROTRIFLUOROETHANE. Prolonged breathing of vapor should be
avoided. The solvent should not be used near heat or open flame; the products of
decomposition are toxic and irritating. Since TRICHLOROTRIFLUOROETHANE
dissolves natural oils, prolonged contact with skin should be avoided. When
necessary, use gloves which the solvent cannot penetrate. If the solvent is taken
internally, consult a physician immediately.
WARNING
When the output ground is floated above Power Line Ground, all BNC connectors
will be at the offset voltage.
a/(b blank)

TM 11-6625-2495-14&P
This manual contains copyrighted material which is reproduced by permission of the HEWLETT-PACKARD Company.
TECHNICAL MANUAL HEADQUARTERS
DEPARTMENT OF THE ARMY
No. 11-6625-2495-14&P WASHINGTON, DC,
4 August 1980
OPERATOR’S, ORGANIZATIONAL, DIRECT SUPPORT,
AND GENERAL SUPPORT MAINTENANCE MANUAL,
(INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS)
FOR
GENERATOR, SIGNAL SG-747/U
(HEWLETT-PACKARD 3300A)
(NSN 6625-00-118-6736)
REPORTING OF ERRORS
You can improve this manual by recommending improvements using DA Form
2028-2 located in the back of the manual. Simply tear out the self-addressed form,
fill it out as shown on the sample, fold it where shown, and drop it in the mail.
If there are no blank DA Forms 2028-2 in back of your manual, use the standard
DA Form 2028 (Recommended Changes to Publications and Blank Forms) and
forward it to the Commander, US Army Communications and Electronics Materiel
Readiness Command, ATTN: DRSEL-ME-MQ, Fort Monmouth, NJ 07703.
In either case, a reply will be furnished direct to you.
TABLE OF CONTENTS
SECTION Page
0 INTRODUCTION............................................................................ 0-1
0-1. SCOPE................................................................................... 0-1
0-2. INDEXES OF PUBLICATIONS.............................................. 0-1
0-3. FORMS AND RECORDS....................................................... 0-1
0-4. REPORTING EQUIPMENT IMPROVEMENT
RECOMMENDATIONS (EIR) ................................................ 0-1
0-5. ADMINISTRATIVE STORAGE .............................................. 0-1
0-6. DESTRUCTION OF ARMY ELECTRONICS MATERIAL...... 0-1
This manual is an authentication of the manufacturer’s commercial literature which through usage, has been found to
cover the data required to operate and maintain this equipment. The manual was not prepared in accordance with military
specifications and AR 310-3, the format has not been structured to consider levels of maintenance.
i

TM 11-6625-2495-14&P
TABLE OF CONTENTS (Continued)
Section Page
I GENERAL INFORMATION........................1-1
1-1. General..........................................1-1
1-5. Electronic Frequency Control........1-1
1-7. Output System...............................1-1
1-9. Instrument and Manual
Identification............................1-1
Section Page
II INSTALLATION..........................................2-1
2-1. Introduction....................................2-1
2-3. Initial Inspection.............................2-1
2-5. Power Requirements.....................2-1
2-7. Grounding Requirements..............2-1
2-10. Installation.....................................2-1
2-12. Bench Mounting ............................2-1
2-14. Rack Mounting ..............................2-1
2-16. Repackaging for Shipment............2-1
Section Page
III OPERATING INSTRUCTIONS..................3-1
3-1. Introduction....................................3-1
3-3. Controls and Indicators .................3-1
3-5. Turn On Procedure........................3-1
3-7. Operating Instructions...................3-1
Section Page
IV THEORY OF OPERATION........................4-1
4-1. Introduction....................................4-1
4-3. General Description.......................4-1
4-13. Schematic Theory .........................4-2
4-14. Frequency Control Network...........4-2
4-17. Current Sources............................4-2
4-19. Triangle Integrator.........................4-2
4-21. Voltage Comparator
Multivibrator ............................4-2
4-23. Sine Wave Synthesizer.................4-2
4-25. Output Amplifiers...........................4-2
4-27. Power Supply................................4-3
4-30. Oven..............................................4-3
Section Page
V MAINTENANCE.........................................5-1
5-1. Introduction....................................5-1
5-3. Performance Checks.....................5-1
5-5. Dial Accuracy.................................5-1
5-7. Distortion Check............................5-1
5-8. Frequency Response....................5-1
5-10. Maximum Output Level,
No Load ..................................5-1
Section Page
V MAINTENANCE (Cont’d)
5-13. Maximum Output Level,
Loaded.................................... 5-1
5-16. Square Wave Response............... 5-2
5-18. Sync Output .................................. 5-2
5-19. Remote Frequency Control
Check ..................................... 5-2
5-20. Channel B-A Check ......................5-3
5-21. Adjustment and Calibration........... 5-3
5-22. Cover Removal ............................. 5-3
5-23. Power Supply Adjustments........... 5-3
5-26. Power Supply Ripple Check.......... 5-3
5-27. Power Supply Regulation Check... 5-3
5-28. Oven Regulation. .......................... 5-3
5-29. Frequency Symmetry Adjust......... 5-3
5-32. Current Source Adjust................... 5-5
5-33. Dial Adjustment............................. 5-5
5-34. Dial Calibrate................................. 5-5
5-38. Distortion Adjust............................ 5-6
5-39. DC Output Level Adjust ................ 5-6
5-41. Square Wave Adjust..................... 5-6
5-43. Repair Procedures........................ 5-6
5-44. Servicing Etched Circuit Boards ... 5-6
5-46. Servicing Rotary Switches............ 5-7
5-48. Replacement of Factory
Selected Components............ 5-7
5-50. Troubleshooting Procedure........... 5-7
5-54. Malfunction Isolation Plug............. 5-7
5-56. Precautions................................... 5-8
5-59. Troubleshooting Tree.................... 5-8
5-62. Troubleshooting Tables ................ 5-10
Section Page
VI CIRCUIT DIAGRAMS ................................ 6-1
6-1. Introduction ................................... 6-1
6-3. Schematic Diagrams..................... 6-1
6-4. Component Location Diagrams .... 6-1
6-5. Plug-In Receptacle........................ 6-1
Section Page
VII REPLACEABLE PARTS............................ 7-1
7-1. Introduction ................................... 7-1
7-4. Ordering Information..................... 7-1
7-6. Non-Listed Parts ........................... 7-1
Appendix
A References................................................. A-1
B Not Applicable.
C Not Applicable.
D Maintenance Allocation.............................. D-1
LIST OF TABLES
Number Page
1-1. Specifications.............................................1-0
5-1. Required Test Equipment...........................5-0
5-2. Power Supply Adjustments.........................5-3
5-3. Integrator Feedback Capacitance..............5-7
Number Page
5-4. Troubleshooting Aid................................... 5-8
5-5. Maintenance Correlation Table.................. 5-10
5-6. Factory Selected Components................... 5-11
7-1. Replaceable Parts...................................... 7-2
7-2. Part No - National Stock
No. Cross Reference Index.................. 7-9
ii

TM 11-6625-2495-14&P
LIST OF ILLUSTRATIONS
Number Page
1-1. Model 3300A Function Generator..............1-0
3-1. Description of Front and Rear Panel
Controls and Connectors.......................3-0
4-1. Block Diagram............................................4-1
5-1. 600 ohm or 50 ohm Load Output Test
Setup.....................................................5-2
5-2. Remote Frequency Control Test Setup......5-2
5-3. Adjustment Point Location..........................5-4
5-4. Voltage Monitoring Points Top and
Bottom...................................................5-4
5-5. Symmetry Adjustment................................5-5
5-6. DC Output Level Adjust Test Setup ...........5-5
Number Page
5-7. Malfunction Isolating Plug.......................... 5-8
5-8. Troubleshooting Tree................................. 5-9
5-9. Normal Oscillator Wave Forms.................. 5-10
6-1. 3300A Top and Bottom Views ...................6-2
6-2. Oscillator Circuit Schematic (A11, A13
and A14)................................................ 6-3
6-3. Range Switch Connections to Plug-In Unit 6-4
6-4. Output Amplifiers Schematic
(A15 and A16)....................................6-5/6-6
6-5. Power Supply Schematic (A12 and A11) 6-7/6-8
6-6. J6 Plug-In Receptacle................................ 6-9
7-1. Modular Cabinet Parts............................... 7-0
iii

TM 11-6625-2495-14&P
SECTION 0
INTRODUCTION
0-1. SCOPE.
This manual describes Generator, Signal SG-747/U (HP-3300A) (fig. 1-1) and provides maintenance instructions.
Throughout this manual, SG-747/U is referred to as the Hewlett-Packard HP-3300A Function Generator.
0-2. INDEXES OF PUBLICATIONS.
a. DA Pam 310-4. Refer to the latest issue of DA Pam 310-4 to determine whether there are new editions,
changes, or additional publications pertaining to the equipment.
b. DA Pam 310-7. Refer to DA Pam 310-7 to determine whether there are modification work orders (MWO’s)
pertaining to the equipment.
0-3. FORMS AND RECORDS.
a. Reports of Maintenance and Unsatisfactory Equipment. Maintenance forms, records, and reports which are
to be used by maintenance personnel at all levels of maintenance are listed in and prescribed by TM 38-750.
b. Report of Packaging and Handling Deficiencies. Fill out and forward DD Form 6 (Packaging Improvement
Report) as prescribed in AR 735-11-2/NAVSUPINST 4440,127E/AFR 400-54/MCO 4430.3E and DSAR 4140.55.
c. Discrepancy in Shipment Report (DISREP) (SF 361). Fill out and forward Discrepancy in Shipment Report
(DISREP) (SF 361) as prescribed in AR 55-38/NAVSUPINST 4610.33B/AFR 75-18/MCO P4610.19C and DSAR 4500.15.
0-4. REPORTING OF EQUIPMENT IMPROVEMENT RECOMMENDATIONS (EIR).
EIRs will be prepared using DA Form 2407, Maintenance Request. Instructions for preparing EIRs are provided in
TM 38-750, The Army Maintenance Management System. EIRs should be mailed directly to Commander, US Army
Communications and Electronics Materiel Readiness Command, ATTN: DRSEL-ME-MQ, Fort Monmouth, New Jersey
07703. A reply will be furnished directly to you.
0-5. ADMINISTRATIVE STORAGE.
Administrative storage of equipment issued to and used by Army activities shall be in accordance with TM 740-90-
1.
0-6. DESTRUCTION OF ARMY ELECTRONICS MATERIEL.
Destruction of Army Electronics materiel to prevent enemy use shall be in accordance with TM 750-244-2.
0-1

TM 11-6625-2494-14&P
Figure 1-1. Model 3300A Function Generator
Table 1-1. Specifications
AVAILABLE PLUG-IN UNITS: SINE WAVE DISTORTION: <1%. 0.01 Hz to 10
Model 3301A Auxiliary Plug-In. kHz; <3%, 10 kHz to 100kHz on the X10K range.
Model 3302A Trigger Plug-In.
Model 3304A Sweep/Offset Plug-In. SQUARE WAVE RESPONSE: <250 nsec rise and
Model 3305A Sweep Plug-In. fall time on all ranges; <500 nsec rise and fall
time in -A; <1% sag; <5% overshoot at full out-
OUTPUT WAVEFORMS: Sinusoidal, square, and put; <1% symmetry error.
triangle selected by panel switch. (Any two
outputs available simultaneously. TRIANGLE LINEARITY: <1% 0.01 Hz to 10 kHz;
<2%, 10 kHz to 100 kHz at full output; < 1%
FREQUENCY RANGE: 0.01 Hz to 100 kHz in symmetry error.
seven decade ranges. SYNC PULSE OUTPUT: > 10 volts peak-to-peak
FREQUENCY RESPONSE: ± 1%, 0.01 Hz to 10 open circuit, <5 µsec duration. Sync pulse
kHz; ± 3%, 10 kHz to 100 kHz on the X10K occurs at crest of sine and triangle wave.
range. DC STABILITY: Drift: <±0.25%6 of peak-to-peak
DIAL ACCURACY:. ± 1% of maximum dial setting amplitude over a period of 24 hours. (After 30
(1 minor division) 0. 01 Hz to 10 kHz; ±2% of minute warmup).
maximum dial setting (2 minor divisions) 10
kHz to 100 kHz. T. C. 0. 1%/°C. REMOTE FREQUENCY CONTROL: 0 to -10 volts
will linearly change frequency > 1 decade with-
MAXIMUM OUTPUT PER CHANNEL: > 35 volts in a single range. Frequency resetability with
peak-to-peak open circuit; > 15 volts peak-to- respect to voltage ±1% of maximum frequency
peak into 600 ohms; > 2 volts peak-to-peak into on range selected.
50 ohms. POWER: 115 or 230 volts ±10%, 48 to 440 Hz.
OUTPUT ATTENUATORS (both channels): 40 dB Less than 50 watts.
range. DIMENSIONS: (inches and millimeters) 5" high
OUTPUT IMPEDANCE: 600 ohms nominal (both (127 mm), 16" wide (406 mm), 11" deep
channels) ± 20%. (279 mm).
1-0

Model 3300A Section I
SECTION I
GENERAL INFORMATION
1-1. GENERAL.
1-2. The Hewlett-Packard Model 3300A Function
Generator is a solid state instrument useful for most
general purpose frequency testing applications. Three
output waveforms are available from front panel
connectors; sine, square, and triangle. A sync pulse is
also available from a rear panel connector.
1-3. The -hp- Model 3300A Function Generator is a
type of relaxation oscillator. The triangle and square
wave voltage functions are inherent in the oscillatory
system. The sine wave is produced by synthesizing the
triangle wave.
1-4. The -hp- Model 3301A Auxiliary Plug-in or
another 3300A plug-in is required to provide internal
connection for basic unit (main frame) operation.
1-5. ELECTRONIC FREQUENCY CONTROL.
1-6. Frequency of the -hp- Model 3300A can be
controlled by either the front panel frequency dial or an
external voltage applied to a rear terminal connector.
This feature is useful for sweeping filters, amplifiers and
other frequency-dependent devices and for externally
programming frequencies for production testing. An
input voltage of approximately -0. 5 to -10 volts will
linearly control the frequency over any one range (one
decade).
If desired the frequency can be controlled over more
than one decade, by applying a +0.3 to -10 volts to the
FREQUENCY CONTROL BNC. A +0. 3 to -10 V input
will linearly control the frequency over approximately a
50:1 range.
1-7. OUTPUT SYSTEM.
1-8. The -hp- Model 3300A has two completely
separate output channels. Each output is dc coupled
and can be fully floating with respect to power line
ground. An internal shield reduces radiated interference
and provides common mode rejection with floating
output. Separate connectors on the rear panel provide
terminals for circuit ground ( ), output ground ( ),
shield ground ( ), and power line ground ( ). The
output ground may be floated from power line ground by
up to +250 volts. Any two of the three waveforms are
available simultaneously from the front panel connectors.
1-9. INSTRUMENT AND MANUAL
IDENTIFICATION.
1-10. Hewlett-Packard uses a two-section serial
number. The first section (prefix) identifies a series of
instruments. The last section (suffix) identifies a
particular instrument within this series. If a letter is
included with the serial number, it identifies the country in
which the instrument was manufactured.
1-11. If the serial prefix of your instrument differs from
the one on the title page of this manual, a change sheet
will be supplied to make this manual compatable with
newer instruments or the backdating information in
Appendix C will adapt this manual to earlier instruments.
All correspondence with Hewlett-Packard should include
the complete serial number.
1-1

Model 3300A Section II
SECTION II
INSTALLATION
2-1. INTRODUCTION.
2-2. This section contains information and
instructions necessary for the installation and shipping of
the Model 3300A Function Generator. Included are initial
inspection procedures, power and grounding
requirements, installation information, and instructions
for repackaging for shipment.
2-3. INITIAL INSPECTION.
2-4. This instrument was carefully inspected both
mechanically and electrically before shipment. It should
be physically free of mars or scratches and in perfect
electrical order upon receipt. To confirm this, the
instrument should be inspected for physical damage in
transit. Also check for supplied accessories and test the
electrical performance of the instrument using the
Performance Checks outlined in Section V.
2-5. POWER REQUIREMENTS.
2-6. The Model 3300A can be operated from any
source of 115 or 230 volts (* 109%), at 48 - 440 Hz.
With the instrument disconnected from the ac power
source, move the slide switch (located on the rear panel)
until the desired line voltage appears. Power dissipation
is approximately 50 watts.
2-7. GROUNDING REOUIREMENTS.
2-8. To protect operating personnel, the National
Electrical Manufacturers’ Association (NEMA)
recommends that the Instrument panel and cabinet be
grounded. All Hewlett-Packard instruments are
equipped with a three -conductor power cable which,
when plugged into an appropriate receptacle, grounds
the instrument. The offset pin on the power cable three-
prong connector is the ground wire.
2-9. To preserve the protection feature when
operating the instrument from a two-contact outlet, use a
three-prong to two-prong adapter and connect the green
pigtail on the adapter to ground.
2-10. INSTALLATION.
2-11. The Model 3300A is fully transistorized;
therefore, no special cooling is required. However, the
instrument should not be operated where the ambient
temperature exceeds 55°C (131F).
2-12. BENCH MOUNTING.
2-13. The Model 3300A is shipped with plastic feet and
tilt stand in place, ready for use as a bench instrument.
2-14. RACK MOUNTING.
2-15. The Model 3300A may be rack mounted by
using the 5" Rack Mount Kit (-hp- Part No. 5060-0775).
Instructions for the conversion are included with the kit.
The rack mount for the Model 3300A is a standard width
of 19 inches.
2-16. REPACKAGING FOR SHIPMENT.
2-17. The following paragraphs contain a general
guide for repackaging of the instrument for shipment.
Refer to Paragraph 2-18 if the original container is to be
used: 2-19 if it is not. If you have any questions, contact
your local -hp- Sales and Service Office. (See Appendix
B for office locations).
NOTE
If the instrument is to be shipped to
Hewlett-Packard for service or repair,
attach a tag to the instrument
identifying the owner and indicate the
service or repair to be accomplished;
include the model number and full
serial number of the instrument. In
any correspondence, identify the
instrument by model number, serial
number and serial number prefix.
2-18. If original container is to be used, proceed as
follows:
a. Place instrument in original container if
available. If original container is not available, one can
be purchased from your nearest -hp- Sales and Service
Office. b. Ensure that container is well sealed with
strong tape or metal bands.
2-19. If original container is not to be used, proceed as
follows: a. Wrap instrument in heavy paper or plastic
before placing in an inner container.
b. Place packing material around all sides of
instrument and protect panel face with cardboard strips.
c. Place instrument and inner container in
heavy carton or wooden box and seal with strong tape or
metal bands.
d. Mark shipping container with "DELICATE
INSTRUMENT, " "FRAGILE", etc.
2-1

Section II Model 3300A
(1) 115V/230V Slide Switch: S2 makes proper
connections in primaryof input transformer for
selected input line voltage.
(2) Power Input Jack: J1, male receptacle for input
power cable.
(3) POWER Pushbutton: S1, a on-off switch which
illuminates when in the on position and power is
applied to the instrument.
(4) RANGE Switch: S3, a seven position rotary
switch which selects frequencydetermining
feedback parameters in the basic oscillatory
circuit.
(5) FREQUENCYDial: R4, a linear dial which
controls frequencywithin the decade selected by
the RANGE Switch (4).
(6) Vernier FrequencyControl: a fine frequency
adjustment knob.
(7) CHANNEL A Function Switch: S4, a four position
rotaryswitch which selects the desired OUTPUT
(10).
(8) CHANNEL B Function Switch: S5, a five position
rotaryswitch which selects the desired OUTPUT
(11).
(9) AMPLITUDE Controls: R12 and R9 attenuators
which varythe output level of the respective
channels.
(10) and (11)
OUTPUT Connectors: J2 and J3, BNC jacks for
connection to the respective outputs of the
function generator.
(12) FREQUENCYCONTROL: J5, a BNC jack for
applying external frequency control voltage.
(13) SYNC OUT: J4, a BNC jack for connection to
sync pulse which occurs at the crests of the sine
and triangle wave.
(14) FREQ DIAL-FREQ CONTROL Shorting Bar:
completes the circuits to the FREQUENCYDial
for internal frequency control.
(15) Common Grounding Straps: ties circuit, output,
and shield grounds to power-line ground. Should
be connected unless otherwise specified.
Figure 3-1. Description of Front and Rear Panel Controls and Connectors
3-0

Model 3300A Section III
SECTION III
OPERATING INSTRUCTIONS
3-1. INTRODUCTION.
3-2. This section consists of instructions and
information necessary for the operation of the -hp- Model
3300A Function Generator.
3-3. CONTROLS AND INDICATORS.
3-4. Each operating control and connector located on
the 3300A is identified and described in Figure 3-1. The
description of each component is keyed to an illustration
of that component.
3-5. TURN ON PROCEDURE.
NOTE
One of the plug-ins must be in place
and locked in before the 3300A is
turned on. To remove a plug-in, turn
off the 3300A and turn the LOCK knob
fully counter-clockwise. This unlocks
the plug-in and pushes it part way out
for ease of removal. To install a plug-
in, turn the LOCK knob fully counter -
clockwise and push into place in the
3300A until it hits the stop, then turn
the LOCK knob fully clockwise.
3-6. To turn on the Model 3300A, proceed as follows:
(Refer to Figure 3-1).
a. Set 115/230 V slide switch (1) to line voltage
to be used, and check for proper value fuse
(.6 amp slow-blow for 115 volt operation, .4
amp slow-blow for 230 volt operation).
b. Connect Power Input Jack (2) to the ac line
voltage with the power cord furnished with
instrument.
c. Depress POWER button (3); ensure that
light in button illuminates.
3-7. OPERATING INSTRUCTIONS.
NOTE
For small signal applications to obtain
optimum signal to noise performance,
use an external 20 dB attenuator.
3-8. To operate the Model 3300A locally using the
FREQUENCY dial, proceed as follows: (See Figure 3-1).
a. Select desired frequency by settings RANGE
Switch (4) and FREQUENCY Dial (5).
b. Select desired function by setting CHANNEL
A and/or CHANNEL B Function Switch (7) or
(8). PLUG-IN position is used for plug-in
function(s).
c. Set AMPLITUDE controls (9) for desired
output level at the OUTPUT connectors(10)
or (11).
3-9. To control the frequency of the Model 3300A
externally (remotely) proceed as follows:
a. Remove FREQ DIAL-to-FREQ CONTROL
shorting bar (14).
CAUTION
VOLTAGE APPLIED TO FREQ
CONTROL BNC SHOULD BE LIMITED
TO A VALUE BETWEEN +0.3 AND -15
VOLTS. VOLTAGES OUTSIDE THIS
RANGE WILL DAMAGE THE
INSTRUMENT.
b. Apply a negative dc voltage from -0.5 to -10
volts to the FREQUENCY CONTROL BNC
(12).
NOTE
-0.5 to -10 volts will linearly control the
frequency over one decade of range
selected. A +0.3 to -10 volts will
linearly control the frequency over
50:1 range.
c. Select desired frequency range and set
amplitude of externally applied voltage for
desired frequency.
d. All 3300A controls except the FREQUENCY
dial are operated in the same manner as in
Paragraph 3-8.
3-10. To dc offset the output function of the 3300A with
either the 3301A or 3302A Plug-in, proceed as follows:
a. Remove CKT GND-to-OUTPUT GND
shorting bar (15).
CAUTION
DO NOT EXCEED ± 25 V DC OFFSET
VOLTAGE BETWEEN OUTPUT
GROUND AND CIRCUIT GROUND.
b. Connect the desired dc offset voltage, up to
3-1

Section III Model 3300A
± 25 V, between CKT GND and the
common grounds. OUTPUT GND, SHIELD
GND, and PWR LINE GND should be
shorted together (15).
c. If more than ± 25 V dc offset is desired,
short CKT GND. OUTPUT GND, and
SHIELD GND together (15). Up to ± 250 V
dc may be applied between this common
ground and PWR LINE GND.
WARNING
WHEN THE OUTPUT GROUND IS
FLOATED ABOVE POWER LINE
GROUND. ALL BNC CONNECTORS
WILL BE AT THE OFFSET VOLTAGE.
3-2

Model 3300A Section IV
SECTION IV
THEORY OF OPERATION
4-1. INTRODUCTION.
4-2. This section contains a description of the theory
of operation of the -hp- Model 3300A Function Generator
with the -hp- Model 3301A Auxiliary Plug-in.
4-3. GENERAL DESCRIPTION.
4-4. The Model 3300A contains a frequency control
network, two current sources, a triangle integrator, a
voltage comparator multivibrator, a sine wave synthesizer
and output amplifiers. (Refer to Figure 4-1
4-5. The Model 3301A Auxiliary Plug-in provides
internal connections which facilitate Model 3300A
operation.
4-6. The voltage comparator multivibrator, current
sources and triangle integrator form the basic function
generating loop. The voltage comparator multivibrator
changes state at predetermined limits on the positive and
negative slopes of the output of the triangular integrator.
This change of state shuts off the upper current source,
reverses the input to the triangle integrator. A cycle is as
follows: when the amplitude of the positive slope of the
triangle wave reaches the upper predetermined limit of
the voltage comparator multivibrator, the multivibrator
changes state. This change of state reverses the current
into the triangle integrator through control of the upper
current source which causes the output of the integrator
to decrease. The decrease continues until the amplitude
of the negative slope reaches the lower predetermined
limit. At this point, the voltage comparator multivibrator
changes state and again reverses the direction of current
at the input of the integrator and causes the output of the
integrator to rise. This rise continues until the voltage
comparator multivibrator again changes state thus
completing the cycle.
4-7. The frequency control network, governed
internally by the FREQUENCY Dial or externally through
the FREQUENCY CONTROL, determines the amount of
current in the current sources, which varies the frequency
as follows: an increase or decrease in input current
increases or decreases the slope of the triangle wave,
respectively. (A change in direction of input current
reverses the slope. ) Frequency will increase if the + and
- slopes are increased, as less time is required for the +
or - slope of the triangle wave to reach the predetermined
limits in the voltage comparator multivibrator.
4-8. The sine wave is synthesized from the triangle
wave by a nonlinear network. This network consists of
resistors and diodes biased so different diodes conduct
during different voltage levels of the triangle wave. These
diodes, when conducting, provide additional shunt paths
within the network. Each additional shunt path changes
the slope of the triangle wave so that the wave is shaped
to a sine wave.
4-9. The output amplifiers are dc coupled and fully
floating with respect to power line ground. CHANNEL A
and CHANNEL B amplifiers are identical and use a
differential amplifier at the input. To maintain the same
peak-to-peak amplitude regardless of function selected,
the overall closed loop gain of the amplifier is varied with
function selection.
Figure 4-1. Block Diagram
4-1

Section IV Model 3300A
4-10. The sync pulse is produced by an RC
differentiating network. The negative pulse at the output
is in phase with the positive crest of the sine and triangle
wave.
4-11. Power Supply (Refer to Figure 6-5) can operate
on either 115 or 230 volts input and delivers 3 pairs of
voltages, +40V, ±26.5V, and +20V. The 40 volt supply
provides power for the oven heater. The 26.5 volt
supplies are regulated and the 20 volt supplies are double
regulated.
4-12. Critical temperature sensitive components are
housed within an oven in which the temperature is
maintained at approximately 800 C (1760 F).
4-13. SCHEMATIC THEORY.
4-14. FREQUENCY CONTROL NETWORK.
4-15. (Refer to Figure 6-2) The FREQUENCY dial (R4)
in conjunction with the RANGE switch (S3) provides
internal frequency control. The basic frequency equation
can be expressed as F= i
2C ∆e out
where i is the current to the triangle integrator, C is the
triangle integrator feedback capacitor and e out is the
peak-to-peak voltage of the triangle wave.
4-16. The position of the RANGE switch determines the
integrating capacitor C. The FREQUENCY dial or
external control voltage determines the current i. The
frequency control voltage is applied to the current control
transistor Al IQ5, which establishes the amount of current
available to the triangle integrator from the current
sources AllQ6 and AllQ7.
4-17. CURRENT SOURCES.
4-18. The state of current source A11Q6 is controlled
by the voltage comparator multivibrator, and in turn,
controls the direction of the current in the input of the
triangle integrator. When A11Q6 is on, a current, 2 i,
flows through it and divides, i into the integrator and i
through current source A11Q7. When the bi-stable
multivibrator changes state and gates A11Q6 off, 2 i no
longer flows; however, the current through A11Q7
remains the same. Therefore, a current equal to i but
opposite in direction flows from the triangle integrator
input.
4-19. TRIANGLE INTEGRATOR.
4-20. The triangle integrator consists of an impedance
converter A11Q8 (a field effect transistor), a differential
amplifier A13Q1 and A13Q2, an emitter follower A13Q3,
diode A13CR1, and the capacitive feedback network: this
circuit integrates the constant current inputs into the
positive and negative slopes which make up the triangle
wave. The triangle wave is applied to the inputs of the
output amplifiers, sine wave synthesizer and voltage
comparator multivibrator.
4-21. VOLTAGE COMPARATOR MULTIVIBRATOR.
4-22. The voltage comparator multivibrator consists of
a voltage comparator switching network, A14Q8,
A14CR13 and A14CR14; a bi-stable multivibrator A14Q9
and Q10 and an emitter follower A14Q11. A14CR19 and
R45 provide a low resistive path to ensure rapid rise and
fall time of the square wave in the event the capacitance
of the load is high. When the positive slope of the triangle
wave reaches +20 volts, A14CR13 is turned on. A14Q9
is then turned on which turns A14Q10 off. The rise in the
collector voltage of A14Q10 is coupled through emitter
follower A14Q11 and through A14CR20 and A14CR21
into the emitter circuit of A11Q6, and turns it on. The
output slope then becomes negative. A11Q6 remains on
until the negative slope reaches zero volts. At the zero
point on the negative slope A14CR14 is turned on which
causes the bi-stable multivibrator to change state so that
A14Q9 is now off and A14Q10 is on. The decrease in
A14Q10 collector voltage gates the current source,
A11Q6, off which reverses the integrator input current.
The positive slope then begins increasing toward the
upper limit, +20 volts. The output of the emitter follower is
differentiated by A14C7 and A14R48 to provide the sync
output. A negative sync pulse occurs at the crest of sine
and triangular wave, see Figure 4-1.
4-23. SINE WAVE SYNTHESIZER.
4-24. (See Figure 6-2) The sine wave synthesizer
comprises four control transistors, the biased diodes with
associated voltage dividers, a differential amplifier
A14Q5, A14Q6 and the output amplifier A14Q7. A14R17
andA14R29 adjust the operating points of the voltage
dividers to minimize distortion. The diodes are biased by
the four control transistors A14Q1 through A14Q4 and the
voltage dividers to provide twelve different current paths
in the input to the differential amplifier as the triangle
wave progresses. Each slope of the triangle wave is
modified in twelve steps so that the waveform appearing
at the base of A14Q5 approximates a sine wave. The
sine wave synthesizing network is isolated by the
differential amplifier A14Q5 and A14Q6 and amplifier
A14Q7.
4-25. OUTPUT AMPLIFIERS. Figure 6-4).
4-26. The etched circuit assemblies A15 and A16 are
identical. CHANNEL A and CHANNEL B differ due to the
-A output of CHANNEL B. The input for CHANNEL B with
its function switch in -A position, A16 Pin 5, is taken from
the junction of A15R20 and R21, XA15 Pin 11. The
output amplifiers are variable gain amplifiers. Gain is
varied by changing the amount of feedback for the
different functions. The following reference designators
should be prefixed by applicable assembly number. The
feedback is varied by resistors R1 through R5 and R23
C8 combination, to maintain equal peak-to-peak
amplitude of the various functions for a given
AMPLITUDE control setting. A differential amplifier, Q1
and Q2, make up the first stage followed by two additional
amplifiers Q3 and Q4. The trimmer C2 in the feedback
network is used to shape the square wave. The
AMPLITUDE control provides a nominal 600 ohms output
impedance, independent of amplitude control setting.
4-2

Model 3300A Section IV
4-27. POWER SUPPLY (Figure 6-5).
4-28. The power supply consists of two full wave
rectifiers CR1 thru CR4 and four series regulated
supplies. AllCR1 provides a stable reference for the two
negative regulated supplies which in turn are the
references for the two positive regulated supplies. The
two 20 volt supplies are double regulated. The operation
of the four supplies is similar: A differential amplifier
senses and amplifies any change. The change is
applied through a driver stage to the series regulator
which then changes its conduction to oppose the
change.
4-29. Operation of the positive and negative supplies
is similar. Diodes CR2 thru CR5 and CR7 thru CR9
determine the maximum current permitted to flow in the
series regulating transistors. Referring to Figure 6-5,
+26.5 volt supply, it can be seen that an increase in
current through R5 and R6 increases the overall forward
bias on the diode network CR2 thru CR5. The
magnitude of this forward bias is determined by the sum
of the forward biased base-emitter diode voltage of Q1
and Q2 in addition to the voltage drop across the R5-R6
combination. When this forward bias increases to a level
sufficient to allow the diodes to conduct, any increase in
the collector current of Q4 will pass through the diodes
and not enter the base of Q2. This, in thru, limits the
maximum current in the series regulating transistors.
4-30. OVEN.
4-31. (See Figure 6-5.) The desired oven temperature
is automatically maintained by a thermal control loop.
The loop consists of a thermistor, a signal amplifier, a
power amplifier, and the heater resistors. The operation
of the loop is as follows: The resistance of RT1
(thermistor) decreases with an increase in temperature
which causes the base current of A11Q9 to increase.
The corresponding decrease of A11Q9 collector voltage
is coupled into the base circuit of the power amplifier Q7.
The collector current of Q7 then decreases which
decreases the current through the heater resistors
generating less heat and the temperature decreases.
The response of the loop is improved by the physical
location of A11R27 in close proximity to the thermistor.
4-3

Section V Model 3300A
Table 5-1. Required Test Equipment
Instrument Type Required Characteristics Use Recommended Instrument
Electronic Counter Range: dc to 100 kHz Performance Checks, -hp- 5245L Electronic
Accuracy: 0.1% Adjustment and Counter with 5262A Plug-
Calibration in Time Interval Unit
Distortion Analyzer Range: 10 Hz to 100kHz Performance Checks -hp- Model 331A Distortion
Freq. Accuracy: +2% Analyzer
Sensitivity: 0.3%fullscale
Input: 1 volt rms
Oscilloscope Sensitivity: 50 mV/cm Performance Checks, -hp- 175A Oscilloscope
Bandwidth: dc to 30 MHz Adjustment with -hp- Plug-in 1750B
Calibration, Repair Vertical Amplifier
Probe 10:1 Bandwidth: dc to 30 MHz Performance Checks, -hp- 10001A Probe 10:1
Division Accuracy: ±2% Adjustment and
Calibration, Repair
DC Voltmeter Accuracy: + 1% F. S. Adjustment and -hp- 3440A Digital Volt-
Range: 10 mV to 50 V Calibration, Repair meter with Plug-in -hp-
Input Impedance: 10 MΩModel 3443A
Resistor 600 ohms Performance Checks -hp- Part No. 0730-0010
1/4 watt
+5%
Resistor 50 ohms Performance Checks -hp- Part No. 0683-5105
1/4 watt
+5%
Resistor 20 K Adjustment and -hp- Part No. 0686-2035
1/4 watt Calibration
+5%
Capacitor 1 µF 50 V Adjustment and -hp- Part No. 0160-0859
Calibration
Variable Line Voltage Range: 100 to 130 V Performance Checks Superior Type UCIM
Transformer
DC Power Supply Range: 0 - 10 volts, 500 mA Performance Checks, -hp- 723A Power Supply
Adjustment and
Calibration
AC Voltmeter Range:10 Hz to 4 MHz Adjustment and -hp- 400F/FL Voltmeter
30 mV to 300 V Calibration
full scale
Printed Circuit
Extender Board 15 Pin Repair -hp- Part No. 5060-0049
Printed Circuit
Extender Board 22 Pin Repair -hp- Part No. 5060-0630
5-0

Model 3300A Section V
SECTION V
MAINTENANCE
5-1. INTRODUCTION.
5-2. This section contains information necessary for
the proper maintenance of the -hp- Model 3300A
Function Generator. The required test equipment is
listed in Table 5-1. Test equipment with comparable
characteristics can be substituted if recommended
equipment is not available.
5-3. PERFORMANCE CHECKS.
5-4. The performance checks are front panel
procedures designed to compare the -hp- Model 3300A
with its specifications. (See Table 1-1). These checks
may be accomplished with either the 3301A Auxiliary
Plug-in or Malfunction Isolating Aid Plug (see Figure 5-7)
installed in the 3300A. These operations should be
completed before any attempt is made to adjust or
calibrate the instrument. Allow a 30 minute warm-up
period before making performance checks. If a
performance check indicates that the instrument does
not meet specifications refer to the applicable paragraph
in the Adjustment and Calibration procedure contained in
this Section. (See Table 5-5).
5-5. DIAL ACCURACY.
a. Test equipment required: Frequency
Counter (-hp- Model 5245L).
b. Connect CHANNEL A OUTPUT to the
frequency counter and set the 3300A
control as follows:
CHANNEL A function switch.........SINE
CHANNEL A AMPLITUDE............mid
position
c. Check frequency with dial at 1 and 10 for
each position of RANGE switch.
d. Accuracy should be * 1% of maximum dial
setting (one minor division) on X. 01
through X1K ranges, and ± 2% of
maximum dial setting (two minor divisions)
on X10K range.
5-6. Since the specification gives % of maximum dial
setting (full scale, the accuracy will always be + 1 or 2
minor divisions at any point on the dial.
5-7. DISTORTION CHECK.
a. Test equipment required: Distortion
Analyzer (-hp- Model 331A).
b. Connect the OUTPUT of CHANNEL A to
distortion analyzer and set 3300A controls
as follows:
FREQUENCY dial......................10
RANGE switch............................X1K
CHANNEL A function switch......SINE
CHANNEL A AMPLITUDE
control.................................mid position
c. Distortion should be less than 1%.
d. Position the RANGE switch to X10K.
Distortion should be less than 3%.
NOTE
The sine function is electronically
synthesized from the triangle
function. Satisfactory performance of
Distortion Check assures symmetry
and triangle linearity.
5-8. FREQUENCY RESPONSE:
5-9. Test equipment required: Oscilloscope (-hp-
Model 175/1750B).
a. Set up convenient reference level on
oscilloscope at 1 kHz.
b. Vary frequency over the entire range except
X10K. Amplitude should vary < ± 1%.
c. Vary frequency over the X10K range.
Amplitude should vary < + 3%.
5-10. MAXIMUM OUTPUT LEVEL, NO LOAD.
a. Test equipment required: Oscilloscope (-hp-
Model 175A/1750B).
b. Connect the OUTPUT of CHANNEL A to
Oscilloscope and set 3300A controls as
follows:
CHANNEL A function switch......SQUARE
CHANNEL A AMPLITUDE.........Max. CW
c. The peak-to peak voltage should be > 35
volts over entire frequency range.
5-11. Repeat 5-10 above with CHANNEL A function
switch set to SINE and TRIANGLE. The minimum peak-
to-peak voltage should remain 35 volts.
5-12. Repeat 5-10 and 5-11 on CHANNEL B.
5-13. MAXIMUM OUTPUT LEVEL, LOADED.
a. Test equipment required: Oscilloscope (-hp-
Model 175A/1750B), 600 ohm, and 50 ohm
resistor, see Table 5-1.
b. Connect OUTPUT of CHANNEL A and 600
ohm resistor as shown in Figure 5-1. Set
the 3300A controls as follows:
FREQUENCY dial...................10
RANGE switch ........................X100
CHANNEL A AMPLITUDE......
control.............................Max. CW
CHANNEL A function switch...SQUARE
c. Peak-to-peak voltage should be > 15 volts.
5-1

Section V Model 3300A
Figure 5-1. 600 ohm or 50 ohm Load Output Test Setup
5-14. Repeat 5-13 on CHANNEL B. Limit should
remain > 15 volts peak-to-peak.
5-15. Repeat 5-13 and 5-14 except load the
instrument with the 50 ohm resistor. CHANNEL A and
CHANNEL B voltage output should be > 2 volts peak-to-
peak.
5-16. SQUARE WAVE RESPONSE.
a. Test equipment required: Oscilloscope (-hp-
Model 175A/1750B) and 10:1 Probe (-hp-
Model 10001A).
b. Connect CHANNEL A OUTPUT without a
load to the oscilloscope using the 10:1
Probe, and set the 3300A controls as
follows:
CHANNEL A function.................SQUARE
FREQUENCY dial......................10
RANGE switch............................X10K
c. Verify: Rise and fall time <250 nano sec.
Sag <1%
Overshoot (full output) <5%
Symmetry error <1%
5-18. SYNC OUTPUT.
a. Test equipment required: Oscilloscope (-hp-
Model 175A/1750B) and 10:1 Probe (-hp-
Model 10001A).
b. Connect SYNC OUTPUT to oscilloscope
and set 3300A controls as follows:
FREQUENCY dial......................10
RANGE switch ...........................X1K
c. Pulse should be > 10 volts peak-to-peak
and < 5 microsecond duration.
5-19. REMOTE FREQUENCY CONTROL CHECK.
a. Test equipment required: DC Power Supply
(-hp- Model 723A) and Oscilloscope (-hp-
Model 175A/1750B).
CAUTION
VOLTAGE APPLIED TO FREQUENCY
CONTROL BNC SHOULD BE LIMITED
TO A VALUE BETWEEN 0 AND
NEGATIVE 15 VOLTS. VOLTAGES
OUTSIDE THIS RANGE WILL
DAMAGE THE INSTRUMENT.
5-17 Repeat 5-16 on CHANNEL B.
Figure 5-2. Remote Frequency Control Test Setup
5-2

Model 3300A Section V
b. Connect the instruments as shown in Figure
5-2. Remove FREQ. DIAL-to-FREQ.
CONTROL shorting bar.
c. Set 3300A controls as follows:
CHANNEL A function switch......SINE
RANGE switch............................X10
CHANNEL A AMPLITUDE.........Max. CW
d. Monitor frequency as power supply is varied
from 0 to -10 volts. Frequency should vary
over the decade, 10 to 100 cycles.
5-20. CHANNEL B-A CHECK.
a. Test equipment required: Oscilloscope (-hp-
Model 175A/1750B).
b. Connect CHANNEL A OUTPUT to one
channel of the oscilloscope and CHANNEL
B OUTPUT to the other channel of the
oscilloscope.
c. Set 3300A controls as follows:
CHANNEL A function switch......SINE
CHANNEL B function switch......-A
d. The output of CHANNEL B should be a sine
wave, but 1800 out of phase with the output
of CHANNEL A.
5-21. ADJUSTMENT AND CALIBRATION.
5-22. COVER REMOVAL.
When it is necessary to repair or adjust the Model
3300A, one or more covers will have to be removed. To
remove either the top or bottom cover, remove the two
phillips screws and slide the cover to the rear.
NOTE
Allow a 30-minute warm-up period
before making any adjustments.
5-23. POWER SUPPLY ADJUSTMENTS.
5-24. The adjustment and calibration procedures are
designed to adjust and calibrate the -hp- Model 3300A
and should be undertaken only if the performance
checks indicate the instrument does not meet
specifications. (See Figure 5-3 for adjustment
identification and indication.)
5-25. The measurement points, adjustments and
voltage limits are given in Table 5-2. Refer to Figure 5-4
for convenient top and bottom chassis location for
monitoring supply voltage. Supplies should be adjusted
in the following order: -26. 5V, +26.5 V, -20 V, +20 V.
The supplies should be rechecked and, if necessary,
readjusted in the same order.
5-26. POWER SUPPLY RIPPLE CHECK.
a. Test equipment required: AC Voltmeter (-
hp- Model 400F/FL).
b. With the AC Voltmeter, check the regulated
power supplies (i26. 5 V and +20.00 V) for
ripple.
c. Ripple should be < 20 millivolts.
5-27. POWER SUPPLY REGULATION CHECK.
a. Test equipment required: DC Voltmeter (-
hp- Model 3440A/3443A) and Variable Line
Voltage Transformer.
b. Apply power to the 3300Athroughthe
variable line voltage transformer.
c. With the DC Voltmeter, check the regulated
power supplies as input voltage to the
3300A is varied from 103 to 127 Vac (207
to 253 Vac). Voltage limits are given in
Table 5-2.
5-28. OVEN REGULATION.
a. After 3300A has been on approximately 30
min, connect a DC Voltmeter between
circuit ground and collector of Q7 (Q9 on
instruments Serial prefixed: 519-, 533-,
609-, 616- and 622-.) Voltage noted should
be approximately 20 volts.
NOTE
This voltage will vary with oven
amplifier transistors.
b. Turn 3300A off for approximately 1 minute,
then turn it on. Voltage should have
decreased to approximately 15 volts.
Voltage should then increase and
overshoot that noted in step a but in time
damp out to approximately 20 V.
5-29. FREQUENCY SYMMETRY ADJUST.
5-30. Lower Frequency Symmetry Adj. (A13R22).
a. Test equipment required: Electronic
Counter (-hp- Model 5245L with 5262A
Time Interval Plug-in).
b. Set 3300A controls as follows:
RANGE Switch...........................X.1
CHANNEL A Function................SQUARE
Output Attenuation.....................Max. CW
FREQUENCY dial......................1
Table 5-2. Power Supply Adjustments
POWER MEASUREMENT ADJUSTMENTS VOLTAGE
SUPPLY POINT LIMITS
+40 ANY RED WIRE (except on S2) NONE +40±3 V
-40 ANY VIOLET WIRE NONE -40±3 V
-26.5 ANY WHITE/VIOLET WIRE A12R20 -26.5 ± 02 V
+26.5 ANY WHITE/RED WIRE A12R7 +26.5 + .02 V
-20 ANY WHITE/BLACK/VIOLET WIRE A12R26 -20.00+0.01 V
+20 ANY WHITE/BLACK/RED WIRE A12R25 +20.00+. 01 V
5-3