HP 1821A User manual

HP
1821A
TIME BASE AND
DELAY GENERATDR
1821A
0OI'
000
HEWLETT hp PACKARD
HP
1821A

CERTIFICATION
The Heivlett-Packard Company certifies that this instrument was
thoroughly tested and inspected and found to meet its published
specifications ivhen it was shipped from the factory. The Hewlett-
Packard Company further certifies that its calibration measure-
ments are traceable to the U.S. National Bureau of Stayidards to
the extent allowed by the Bureau’s calibration facility.
WARRANTY AND ASSISTANCE
All Hewlett-Packard products are warranted against defects in
materials and workmanship. This warranty applies for one year
from the date of delivery, or, in the case of certain major compo-
nents listed in the operating manual, for the specified period. We
will repair or replace products which prove to be defective during
the warranty period provided they are returned to Hewlett-
Packard. No other warranty is expressed or implied. We are not
liable for consequential damages.
Service contracts or customer assistance agreements are available
for Hewlett-Packard products that require maintenance and re-
pair on-site.
For any assistance, contact your nearest Hewlett-Packard Sales and
Service Office. Addresses are provided at the back of this manual.

^MANUAL CHANGES
MODEL 1821A
TIME BASE AND DELAY GENERATOR
Manual Serials Prefixed: 809-
Manual Printed: JUNE 1968
Make all changes in this manual according to the Errata below. Also check the following table for your
instrument serial prefix (3 digits) and/or serial number (8 digits) and make any listed change(s) in the manual:
Serial Prefix or Number Make Manual Changes Serial Prefix or Number Make Manual Changes
ERRATA Table 6-2, Replaceable Parts,
A3: Change description to A: sweep time (inci A2 and A4).
Add A4: HP Part No. 01821-61905; TO 1; A: sweep time switch.
C501: Change to HP Part No. 01 60-3355; TO 1; C: fxd poly 1uF
5% 200 vdcw (preferred replacement).
AC504, C526: Change to HP Part No. 0160-3540; TQ 2; C: fxd poly 0.001 uF5% 100 vdcw
(preferred replacement).
AC503, C525; Change to HP Part No. 0160-3541; TQ 2; C: fxd poly 0.01 uF 5% 100 vdcw
(preferred replacement).
AC502, C524; Change to HP Part No. 0160-3542; TQ 2; C: fxd poly 0.01 uF 5% 100 vdcw
(preferred replacement).
LI 02, LI 03, LI 07, L1 10. L201, L302, L305, L306: Change to HP Part No. 9140-0179;
TQ 8; L; fxd 22 uh 10% (Preferred Replacement).
Q412: Change to HP Part No. 5080-0482; Q: Si fet (selected)
(Preferred Replacement).
MISCELLANEQUS;
HP Part No. 01821-01204: Change to Bracket: plug (P2).
HP Part No. 01821-04101 :Change to Plate: mounting (J1).
Page 8-5, Figure 8-4,
L102, L103, L107, L1 10: Change value to 22 uh.
Page 8-7, Figure 8-6,
L201 :Change value to 22 uh.
Page 8-9, Figure 8-7,
L302, L305, L306: Change value to 22 uh.
CHANGE 1Table 6-2, Replaceable Parts,
VR201,VR403: Change to HP Part No. 1902-0688; VR: breakdown, 53.6V.
Page 8-7, Figure 8-6, Schematic,
VR201: Change to 53.6V.
Page 8-11, Figure 8-8, Schematic,
VR403: Change to 53.6V.
Page 8-14, Figure 8-11,
J1: Move -1-1 5V power from pin 21 to pin 20.
CHANGE 2Table 6-2, Replaceable Parts,
Add C108, C304: HP Part No. 0140-0149; TQ 2; C: fxd mica 470 pF 5% 300 vdcw.
Q101: Change to HP Part No. 1854-0215.
R113: Change TQ to 6.
R114, R305: Change to HP Part No. 0757-0442; TQ 6; R: fxd metfim 10 kohms 1% 1/8W,
11 December 1969 R1 40: Delete TQ.
A=Latest additions to this change sheet.
This change sheet supersedes all prior change sheets for this manual. Supplement Afor
01821-90904

Model 1821 APage 2/2
Instrument Serial Prefix Make Manual Changes Instrument Serial Prefix Make Manual Changes
809-03295 &higher 11
821- 11
905- 1,2 1
907- 1,2,3
CHANGE 2(Cont'd) Page 8-5, Figure 8-4, schematic.
Add C108, 470 pf, on S102 between ACS position and ground (next to R1 13).
R1 14: Change value to 10 kohms.
Page 8-9, Figure 8-7, schematic.
Add C304, 470 pf, on S302 between ACS poistion and ground (next to R304).
R305; Change value to 10 kohms.
CHANGE 3Table 6-2, Replaceable Parts,
R103, R301 :Change to hp Part No. 0698-6400; TQ2; R: fxd metfim 900 kohms 1% 1/4 w.

OPERATING AND SERVICE MANUAL
MODEL 1821A
TIME BASE AND DELAY GENERATOR
SERIALS PREFIXED: 809
See Section VII For Instruments
With Other Prefixes
Copyright HEWLETT-PACKARD COMPANY/ CO LOR ADO SPRINGS DIVISION 1966
1900 GARDEN OF THE GODS ROAD, COLORADO SPRINGS, COLORADO, U. S. A.
02591-4 PRINTED: JUNE 1968

Table of Contents Model 1821A
TABLE OF CONTENTS
Section Page
IGENERAL INFORMATION 1-1
1-1. Instrument Description 1-1
1-5. Scope of Manual 1-1
1-7. Instrument Identification •••1-1
1-
9. Manual Changes 1-1
II INSTALLATION 2-1
2-
1. Initial Inspection 2-1
2-4. Claims 2-1
2-7. Repackaging for Shipment •••2-1
2-
10. Preparation for Use 2-1
ni OPERATION 3-1
3-
1. Introduction 3-1
3-3. Controls and Connectors ••••3-1
3-16. Trigger Signal Requirements ••3-2
3-
18. Operating Instructions 3-2
IV PRINCIPALS OF OPERATION 4-1
4-
1. Introduction 4-1
4-6. Main Sweep 4-1
4-8. Block Diagram Description •4-1
4-13. Circuit Details 4-2
4-26. Delayed Sweep 4-3
4-28. Block Diagram Description •4-3
4-32. Circuit Details 4-3
4-
39. Sweep Display 4-4
VPERFORMANCE CHECK AND
ADJUSTMENTS 5-1
5-
1. Introduction 5-1
5-3. Test Equipment 5-1
5-5. Performance Check 5-1
5-9. Preliminary Set-Up 5-1
5-11. Initial Control Setting .... 5-1
5-12. Triggering 5-1
5-13. Trigger Point and Slope •••5-2
5-14. Main Sweep Time 5-2
Section Page
5-15. Main Sweep Vernier 5-2
5-16. Magnified Sweep 5-2
5-17. Delayed Sweep Time 5-2
5-18. Delayed Sweep Vernier • • •5-3
5-19. Delay Time Accuracy ••••5-3
5-20. Delay Time Linearity •• ••5-3
5-21. Jitter 5-3
5-22. Delayed Trigger Output . . .5-3
5-23. Mixed Sweep 5-3
5-24. Single Sweep 5-3
5-25. Adjustments 5-3
5-27. Preliminary 5-3
5-29. Initial Control Settings •... 5-3
5-30. Output Level 5-4
5-31. Trigger Symmetry 5-4
5-32. Main Sweep Length 5-4
5-33. Delayed Sweep Length .... 5-4
5-34. Main Sweep Time 5-4
5-35. Delayed Sweep Time 5-4
5-36. Sweep Comparator •• • •5-5/5-6
VI REPLACEABLE PARTS 6-1
6-1. Introduction 6-1
6-4. Ordering Information 6-1
VII manual changes and options •••7-1
7-1. Manual Changes 7-1
7-5. Options
7-7. Special Instruments 7-1
VIII SCHEMATICS AND TROUBLESHOOTING 8-1
8-1. Introduction .8-1
8-3. Schematic Diagrams .... .8-1
8-6. Component Identification • • .8-1
8-8. Troubleshooting .8-1
8-12. Repair and Replacement •••8-1
11 02591-2

Model 1821A List of Illustrations
List of Tables
LIST OF ILLUSTRATIONS
Number Title Page
1-1. Model 1821A Time Base and
Delay Generator 1-0
1-
2. Sweep Combinations 1-2/2-0
2-
1. Plug-In Mating 1-2/2-0
3-
1. Controls and Connectors 3-0
3-2. Trigger Amplitude Requirements •••3-2
3-3. Main Sweep Operation 3-3
3-4. Mixed Sweep Operation 3-4
3-5. Rise Time Measurements 3-5
3-6. Time Differential Measurements •••3-6
3-
7. Single Sweep Operation and Intensity
Ratio Adjustment 3-7
4-
1. Model 1821ABlock Diagram 4-0
4-2. Main Sweep Circuit Block Diagram •••4-1
4-3. Delayed Sweep Circuit Block Diagram •4-4
4-4. Sweep Displays 4-5
Number Title Page
5-1. Main Triggering Test Set-Up 5-1
5-2. Delayed Triggering Test Set-Up •••5-2
7-
1. Sweep Display Switch 7-0
8-
1. Over -All Troubleshooting Tree 8-3
8-2. Adjustment Location and Component
Identification 8-3
8-3. Component Identification, A1 8-4
8-4. Main Trigger Schematic Diagram •••8-5
8-5. Component Identification, A2 8-6
8-6. Main Sweep Schematic Diagram ••8-7
8-7. Delayed Trigger Schematic Diagram ••8-9
8-8. Delayed Sweep Schematic Diagram •••8-11
8-9. Component Identification, A3 8-12
8-10. Sweep Time Switch Schematic Diagram 8-13
8-11. Plug and Jack connections 8-14
LIST OF
Number Title Page
1-
1. Specifications 1-0
2-
1. Shipping Test Strengths 2-1
3-
1. Trigger Signal Requirements 3-2
5-1. Required Test Equipment 5-0
5-2. Main Sweep Performance 5-2
5-3. Delayed Sweep Performance 5-3
TABLES
Number Title Page
5-4. Main Sweep Time 5-4
5-
5. Delayed Sweep Time 5-4
Performance Check Record .... 5-7/5-8
6-
1. List of Reference Designators and
Abbreviations 6-1
6-2. Replaceable Parts 6-2
8-1. Schematic Diagram Notes 8-2
111
02591-3

Section I
Figure 1-1 and Table 1-1 Model 182 lA
Figure 1-1. Model 182 lA Time Base and Delay Generator
Table 1-1. Specifications
MAIN SWEEP:
RANGE:
0. 1psec/divto 1sec/div, 22 ranges in a1, 2,
5sequence; accuracy ±3%; vernier provides
continuous adjustment between ranges and ex-
tends slowest range to at least 2. 5sec/div;
Horizontal Magnifier, on Model 180- series
Oscilloscopes, expands fastest range to 20
nsec/div (X5) or 10 nsec/div (XIO) with 5%
accuracy.
TRIGGERING:
NORMAL:
Triggering Coupling: DC, AC, ACF, ACS:
AC attenuates signals below approximately
20 Hz; ACF attenuates signals below approxi-
mately 15 kHz; ACS attenuates signals above
approximately 30 kHz.
Internal: see manual for Vertical Plug-In.
External: 0. 5vpk-pkfrom dc to 50 MHz
(depending on Trigger Coupling) increas-
ing to 1Vpk-pk at 90 MHz.
Line: power-line waveform is used for
triggering.
Slope: selectable, positive or negative.
Trigger Point: adjustable ±3 vover selected
trigger signal (±30 vin EXT 10).
AUTOMATIC:
Bright baseline displayed in absence of trig-
jger signal. Triggering is same as normal
except that lower frequency limit of trigger
signal is 40 Hz.
DELAYED SWEEP:
RANGE:
0. 1psec/div to 50 msec/div, 18 ranges in a
1, 2, 5sequence: accuracy ±3%; vernier pro-
vides continuous adjustment between ranges
and extends slowest range to at least 125
msec/div; Horizontal Magnifier, onModel 180-
series Oscilloscopes, expands fastest range to
20 nsec/div (X5)or 10 nsec/div (XIO) with 5%
accuracy.
TRIGGERING:
AUTOMATIC:
Delayed sweep starts automatically at end
of delay time. Slope, Trigger Point and
Trigger Coupling are not selectable.
NORMAL:
Delayed sweep starts on first trigger signal
after delay time.
Trigger Coupling: DC, AC, ACF, ACS:
AC attenuates signals below approximately
20 Hz; ACF attenuates signals below approxi-
mately 15 kHz; ACS attenuates signals above
approximately 30 kHz.
Internal: see manual for Vertical Plug-In.
1-0 02591-3

Model 1821A Section I
Paragraphs 1-1 to 1-10
SECTION I
GENERAL INFORMATION
1-1. INSTRUMENT DESCRIPTION.
1-2. The Hewlett-Packard Model 1821A Time Base
And Delay Generator (shown in Figure l-l)isasweep
generating plug-in unit for the hp Model 180-series Os-
cilloscope. Main sweep speeds are selectable in 22
ranges from 0. 1p,sec/ divto 1sec/div. Avernier pro-
vides continuous adjustment between ranges and will
extend the slowest sweep to at least 2. 5sec/div. The
Magnifier switch on Model 180-series Oscilloscopes
can expand the fastest sweep to 10 nsec/div. Delayed
sweep speeds can be selected with 18 ranges from 0. 1
(isec/ div to 50 msec/div; the delayed vernier provides
continuous adjustment between ranges and extends the
slowest sweep speed to at least 125 msec/div. The
main and delayed sweeps can be used either separately
or combined to obtain adual sweep-speed display.
1-3. The delayed sweep feature of the Model 1821A
permits accurate time measurement between arefer-
ence signal and apoint of interest on acomplex wave-
form or pulse train; it also allows for exact time inter-
val measurement between consecutive pulses in apulse
train or burst. The length of time before the delayed
sweep starts is adjustable. The mixed sweep feature
permits viewing simultaneously the character of an
entire complex waveform and an expanded portion of
the same waveform.
1-4. Single sweep operation is possible for any type
of display. This feature may be used with any sweep
speed to facilitate transient waveform photography.
Normal triggering of the Model 1821A main sweep and
delayed sweep may ^e selected to occur on an internal
signal from the verticalplug-inor on an external sig-
nal up to 90 MHz (requires 0. 5v pk-pk up to 50 MHz,
increasing to Iv at 90 MHz). For the main sweep,
automatic triggering provides abright base line in the
absence of an input signal; for the delayed sweep, auto-
matic triggering starts this sweep at the end of the de-
layed period set. Trigger slope level, and coupling
are controlled from the front panel for both the main
and delayed sweeps. Table 1-1 provides complete
specifications for the Model 1821A and Figure 1-2
illustrates typical displays obtainable with the plug-in.
1-5. SCOPE OF MANUAL.
1-6. This manual provides operating and service in-
formation for the hp Model 1821A Time Base AndDe-
lay Generator. This manual supplements the infor-
mation presented in the Operating and Service Manual
for the hp Model 180-sefies Oscilloscope. For specific
information about any plug- in for the Model 180- series
Oscilloscope, refer to the manual for that plug-in.
1-7. INSTRUMENT IDENTIFICATION.
1-8. Hewlett-Packard uses atwo-section eight-digit
serial number to identify instruments. Thefirstthree
digits (preceding the dash) are the serial prefix which
identifies aseries of instruments; the last five digits
identify aparticular instrument in the series. The
serial number appears on aplate located on the rear
panel. All correspondence with aHewlett- Packard
Sales/Service Office in regard to an instrument should
reference the complete serial number.
1-9. MANUAL CHANGES.
1-10. This manual provides complete information for
any Model 1821A with aserial number prefixed (see
Paragraph 1-7) by the three digits indicated on the title
page. If the serial prefix of the instrument is differ-
ent from that on the title page, a"Manual Changes"
sheet supplied, or Section VH of this manual, will de-
scribe changes which willadapt this manual to provide
correct coverage. Technical corrections (if any) to
this manual, due to known errors in print, are called
Errata and are shown on the change sheet. For in-
formation on manual coverage of any hp instrument,
contact the nearest hp Sales/Service Office (addresses
are listed at the rear of this manual).
Table 1-1. Specifications (Cont'd)
External: 0. 5vpk-pkfrom DC to 50 MHz
(depending on Trigger Coupling) increas-
ing to 1vpk-pk at 90 MHz.
Slope: selectable, positive or negative.
Trigger Point: adjustable ±3vover selected
trigger signal (±30 vin EXT 10).
DELAY:
Time: continuously variable from 0. 1psecto
10 sec; accuracy ±1%; linearity ±0.2%; time
jitter is less than 0. 005% of maximum delay of
each range (1 part in 20, 000).
Trigger Output (at end of delay time): approxi-
mately 1. 5Vpulse with rise time less than 50
nsec from Ik ohm impedance.
MIXED SWEEP:
Dual sweep display in which main sweep drives
first portion of display and delayed sweep com-
pletes display at speeds up to 1, 000 times faster.
INTENSIFIED SWEEP:
The intensified section of the main sweep shows
the time of the delayed sweep. It indicates the
portion of the main sweep to be expanded full
screen in delayed operation.
SINGLE SWEEP:
Frontpanel controls permit single sweep operation.
WEIGHT:
Net, 3-3/4 lbs (1,7 kg). Ship, 6-l/41bs(2, 8kg).
02591-3 1-1

Sections Iand II
Figures 1-2 and 2-1 Model 1821A
Figure 1-2. Waveforms illustrating sweep combinations using Model 1821A: (A) normal sweep; (B) intensified
sweep portion covered by delayed sweep is brightened); (C) delayed sweep (intensified portion of Bis expanded
to full 10 div); (D) mixed sweep (faster delayed sweep drives right portion of display).
PLUG JACK LATCH RELEASE
MiH w*o Ootuwe
mmt/ rim/m amm
VERTICAL
PLUG-IN
BULKHEAD
CONNECTORS LATCH HORIZONTAL
PLUG-IN
I80IA-A-IIB
Figure 2-1. Plug-In Mating
1-2
2-0 02591-3