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VOLUME 13 NUMBER 4 SEPT.-OCTOBER 1973
I
when the unknown oscillator is ad-
justed to stop the motion of the
scope pattern, any errors in the
scope sweep drop out completely.
See Figure 2.
PHASE DETECTOR WITH
STRIP CHART RECORDER:
While the oscilloscope method still
works when comparing very stable
oscillators (for instance, when com-
paring a Rubidium standard to a
Cesium standard) a phase detector
driving a strip chart recorder gives a
more useful record. Since the record
is continuous, the operator can
visually ignore noise and other ob-
vious known discrepancies when
~
making the comparison.
-1 counter or ofother device requires
Calibration acrystal oscillator in a These transmissions can be used to
calibrate an oscillator to a part in 1 0 6
A modified version of the 117A can
be used to make a phase com-
several pieces of equipment plus a or so and can be used to check a parison between an unknown
systematic procedure. First of all, stable oscillator for gross error due kHz standard and the local standard,
as well as the local Stan-
one must have a referencestandard t o some m a l f u n c t i o n . T h i s dard to WWVB. HP has also builtthe
which is more accurate than the procedure is shown in Figure 1.
K05-5060A and K19-5061A linear
'pecification to be met*This usually The HP 5360A Computing Counter phase comparators for making high
takes the form Of an "in house" fie- can be used to measure the OS- resolution comparisons between
quency standard - a quartz Os- cillator frequency of most other 1 0 5 ~ /oscillators, 5 0 6 0 ~ / 5 0 6 1 ~
~
cillator* a Rubidium frequency devices Since it Will resolve 1X 10-10 Cesium standards, 5065A Ruidium
Or a Cesium Beam fie- in one second. Other Counters are standard, and similar high stability
quency standard- The standard is generally not satisfactory for setting sources. The 8405Avector voltmeter
compared to the National Bureau of precision oscillators because even
Standards station WWVB on 60 kHZ On a 10 second gate the count
using an HP model 117A vLF error for a one megahertz signal is
parator for locations within the con- 1 10-7, whereas a good :illator
tinental United States or an ap- ...
. .o
,
can easily have a stabilitv i n tl 1000
I w
propriate receiver to receive one of times better than this
the other world-wide frequency
services for stations outside the U.S.
For example, the H44-117A can be TRIGGERED
used to receive station HBG in OSCILLOSCOPE METHOD:
Prangins, Switzerland. A triggered sweep oscilloscope is
d WWV high frequency transmissions the easiest device to use for setting
should NOT be used for calibrating a one oscillator to agree with another.
high stability oscillator because the Resolution is good; furthermore, the
variations due to noise and doppler oscilloscope gives a continuous in-
shift can introduce more error than dication of both the direction and
10 to 100daysaging of theoscillator. magnitude of error. In addition,
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-_
pq CALIBRATION OF A N OSCILLATOR
WWV 2,'5'-5-10-l~-20-25 MMZ
WWHV 2 5 - 9 - 1 0 - 1 MU2
3
Fig. 2
can also be used t o make h i g h hours later is 3.61. in 1 hour. This A frequency multiplier as shown in
resolution phase comparisons corresponds to a frequency offset of the block diagram of Figure 4 can
between frequency standards as 1 part in 109. Thus the aging rate for also be used to increase the resolu-
outlined i n Application Note this 24-hour period is the difference tion with which a crystal oscillator
AN 77-2, "Precision Frequency between the offsets. This is 2 parts in frequency can be measured in
Corn pa r iso n ." 109 if theoffsetsare both higherthan a given measurement time. The
or both lower than the reference. "times 200" multiplication in this
Figure 3, which is taken from the The aging rate is 4 parts in 109 if one case was achieved b y using a
117A manual, is useful for determin- reading is above and one reading 5245M/5254C. The unknown stand-
ing the offset between two standards below the reference frequency. ard was connected to the EXTER-
when the phase changeand the time The frequency offset chart is NAL standard input on the 5245M.
required for the phase change are determined by noting that an hour The 5245C is tuned to 1.0 GHz and
known. Special templates are sup- contains 3 . 6 lO9ps. Thus dividing
~ the 1 GHz output is taken from the
plied with the 117A VLF comparator this into a given frequency change coax which connects to the center
so this offset can be read without (in ps per hour) will yield the offset. of the 5254C cavity.
charts or calculations. In the first example above, This output signal will be exactly
10.8ps/hour = 3 10-9. 200 times the nominal 5 MHz ex-
For example, assume that on a
particular day the phase change is 3 . 6 109ps/hour
~ ternal standard input. This output
1 0 . 8 ~ s 1 hour. This corresponds
in is measured on a 5254C in a second
to a frequency offset of 3 parts in 109. FREQUENCY MULTIPLIER 5245UM or 5248L/M with a second
Assume that the phase change 24 METHOD: 5254C tuned to .95 GHz.
ELAPSED TiME I11
Fig. 3 Frequency Offset Chart
cMINUTES1HOURS - Fig. 4
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c The counter will
display 50 000 000 Hz
A simple check of the overall sys-
tem can be made by driving the
indicated above by feeding the same
frequency to each input and noting
a difference of zero.
5254C dial to + 950 000 000 Hz EXT STD Input of the first counter
with a standard frequency output
Frequency measured by 2nd of the second counter instead of
5245L/5254C = 1 000 000 000 Hz from the unknown standard. The WARM-UP CYCLE
second counter should then read
Note the resolution is 1 part in 109 50 000 000 *1 Hz or 50 000 000.0 If the crystal oven of a high stability
for a 1-second measuring time and kO.1 Hz, depending on the measure- oscillator is allowed to cool-even
would be 1 part in 1010 for a 10- ment time. for a few minutes-the temperature
second measuring time. For very A difference frequency comparator gradient may stress the quartz plate
high accuracy work, you may want can also be used to compare fre- enough so it has to go through
to drive the time base of the second quency standards. This device mul- another warm-up cycle. Some
counter from a Cesium or Rubidium tiplies the difference in frequency charts of typical (not guaranteed)
reference standard. This measure- between an unknown input and a turn-on curves on the 5245L oscil-
ment system is linear so all chart reference input by decade steps lator both for oven hot and oven
readings are meaningful and fre- until it is large enough to read on cold turn-on are shown in Figures
quency change can be determined an analog meter or display on an 5 through 8 . The oven on the 5245L
by a simple subtraction. oscilloscope. It can be checked as is operating whenever the power
-I XIO-
0 ~ 0 2 0 ~ 0 4 0 w 6 0 1 0
WE V O l . 7 H TIME I U U O W 5 +
APPUEV
4
Fig. 5 Three Typical Counters at Room Temperature, Line Voltage Fig. 6 Three Typical Counters at Room Temperature. Disconnected
Connected, with Counter Switch Off. (Oven Operating) from Line Voltage for more than 48 hours.
LINE VOLTA6E TIM6 IIJ clOUQ5 + I t
AWUED r TIM IU WUE5 +
4 LIk.EVOLThW
APPUCQ
Fig. 7 Four Typical Counters at Room Temperature, Disconnected Fig. 8 Four Typical Counters at Room Temperature. Disconnected
from Line Voltage for more than 48 hours. from line Voltage for more than 48 hours.
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I CALIBRATION OF A N OSCILLATOR
7 8 7 6 5 4 1 2 1 0
TIME 113 M t W
IJ 5*
Fig. 9
cord is energized. A warm-up curve
for the 5245M/105A crystal oscilla- ERROR IN M E A S U R E M E N T FREOUENCY MEASUREMENT: PERIOD MEASUREMENT:
tor, Figure 9, which was measured PRCE,NUGE 10ix F R A r f I CWNT
f TIME BASE ACCURACY ASSUMED
f l COUNT
*TIME BASE ACCURACY
m BE f i PART IN 1 8 FOR
0 TRIGGER ERROR:O 3% i PERIOD
using the Frequency Multiplier Set- THIS EXAMPLE. COUNTED FREOUENCY IS IOMHZ
up, is also included. In this case, 1 1 1
fill@ IHZ IOHZ IOOHZ IKHZ IOWZ IOOKHZ IHHZ IOMHZ IOOMHZ IOOOMHZ IOGHZ IOOGHZ
both the oven and oscillator operate
whenever the power cord is plugged 10% I x 10-1
into a live outlet. I 7. I x 0-2
Once the oscillator has been cali- 0.17. I x 10-3
brated, the easiest way to determine 0.01% I x lo-`
the total error in any measurement
0.001% I x IO-'
is to look for the accuracy chart in
the manual for the counter of in- 0.WOI % I x 10-6
terest. Figure 10 is the accuracy 0.00001% I x 10-1
chart for a 5245L counter. This
0.000001% I x 10-0
chart takes into account all of the
errors in the frequency or period 0.0000001% I x 10-9
IOHZ IOOHZ lKHZ IOKHZ lOOKH7. IMHZ IOMHZ IOOMHZ IOOOMHZ IOGHZ IOOGHZ
modes of operation. Each counter
will have its own error chart so be
sure to use the correct one for your
I Fig. 10 Accuracy Chart
M E A S U R E 0 FREOUENCY
model of counter.
To determine the error, locate the
input frequency being measured on
the horizontal scale. For frequency I
frequency counter. He began his
measurements, move upward to the career with HP in 1951 as a design
appropriate line for the gate time engineer. He was involved with
selected by the front panel control. the 524 counters, AC-4 decoder,
For period average measurements, 218A digital delay generator and
move upward to the appropriate m-
5214L preset counter.
line for the number of periods being Widely recognized as a fre-
averaged. Then move left to read quency standards expert, Marv
the total error, which can be ex- is the author of many contribu-
pressed as a fraction, as a power tions to the electronics industry;
of ten, or as a percentage. his most recent involvement has
Figure 11 shows a typical warm-up been as one of the authors in a
frequency vs time plot for a 10544A McGraw-Hill book, Basic Elec-
oven oscillator. This oscillator, Marv Willrodt, an Applica- tronic Instrument Handbook
which is available as an option in a tions Engineer with the Santa which is edited by Clyde Coombs.
number of HP products, has a fast Clara Division of Hewlett-Pack- He is a stereo sound enthu-
warm-up feature. Note that fre- ard, is currently working on a siast in addition to a photography
quency readings are listed for the user's guide for a new electronic buff.
first few minutes instead of a plot
because of limitations of the mea-
suring technique used.
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ernen t
o -
c.
Service Notes for your instru-
On the next page is a listing ments can be obtained by
of the latest Service Notes avail- using the Service Note Order
able for Hewlett-Packard Form. When the order form is
products. Service Notes contain removed, it can be folded two
information that will help you ways. European customers
should fold it to expose
get the most out of your this address:
purchases. Hewlett-Packard S.A.
Many times design changes or Central Mailing Department
P.O. Box 7550
other improvements are made
Freeport BuiIding
in products currently being SCH IPHOL- Cent rum
manufactured. HP often recom- The Netherlands
mends including these changes For the U.S. and elsewhere,
in products previously sold; fold the order form to expose:
this is done by writing a Service Hewlett-Packard Company
Note for the product. 195 Page Mill Road
Palo Alto, California 94306
OCTOBER 1973
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SERVICE NOTES
MJI Equipment necessary to calibrate and check 3330A/B AUTOMATIC SYNTHESIZER 8640AIB AM-FM SIGNAL GENERATOR
performance of HP Real Time Oscilloscopes. 3330A-3 Serial number 1145A 001 12 and below. 8640A-5/8640B-6.8640A serial prefix 1245A and below.
Modification to prevent power supply oscillations. 86408 serial prefix 1246A and below. Replacement
136A X-Y RECORDER 33308-3 Serial numbers 1305A00260and below. F/Range switch assembly.
136A-2 Serials prefixed 705 and below. Y2 chopper Modification to prevent power supply oscillations. 8640Ad/8640B-7. Serial prefix 1310A and below.
replacement. Improved AM noise performance.
3459A DIGITAL VOLTMETER 8640A-7/8640B-8.8640A serial prefix 1243A and below.
3459A-11 All serials. Replaced the oven controlled 8640B serial prefix 1244A and below. AM
ll5OA PROGRAMMABLE bandwidth improvement.
WAVEFORM PROCESSOR power supply.
8640A-8/8640B-9.8640A serial prefix 1250A and below.
1150A-1 Removal of boards from"B1ue Stripe" program. 8640B serial prefix l25lA and below. Front panel
5216A ELECTRONIC COUNTER
5216A-2 Serial prefix 976 and below. Solution for A4 meter replacement.
1208A, B DISPLAY 8640A-9/8640B-10. Serial prefix 1301A and below.
1208A/ HI 1-2 Serial prefix 1130A and below. Changes decade divider reset problem.
Improvements in AM and pulse circuits.
on storage pulse assembly A4. 8640A-10/8640B-11. 8640A serial prefix 1243A and
lu)8A/H11-3 Serial prefix 1212A and below. 5300A FREQUENCY COUNTER below, 8640B serial prefix 1244A and below.
Modification to improve storage uniformity. 5300A-2 Serial number 1208A02161 and below. Reduction in RFI leakage from front panel.
Modification to prevent thermal runaway. 8640A-11/8640B-12. All serials. R F On/Off switch
5300A-1A All serials. Instructions to measure power modification.
1 3 0 A X-Y DISPLAY line frequency.
1300A/ H82-1 All serial prefixes. Transfer to production 8640A-12. Serial prefix 1313A and below.
option status. Recommended A8 mechanical dial replacement,
1308A-5 Serial prefix 1303A and below. New CRT 5303A 500 MHz COUNTER MODULE
graticule. 5303A-1 Serial prefix 1124A and below. Modification 8654A SIGNAL GENERATOR
1308A-6 Serial prefix 1315A and below. Addition of to install input overload protection. 8654A-1 Serial prefix 1305A and below. Output
heat sinks on X/Y output stage transistors. attenuator replacement.
1309A-4 All serial prefixes. Error in manual change 5310A BATTERY PACK
sheets. 5310A-1 All serials. Precautions for battery replacement.
1309A-5 Serial prefix 1252A and below. New CRT 8660A SYNTHESIZED SIGNAL GENERATOR
graticule. 8660A-13 Serials 1246A00350 and below. 500 MHz
5326/5327 SERIES UNIVERSAL TIMER/ COUNTER amplifer heatsink.
1309A-6 Serial prefix 1318A and below. Addition of 5326A/B/C/5327A/B/C-4 All serials. Modification to
heat sinks on X/Y output stage transistors. 8660A-14 All serials. "The Indirect Generation"
prevent Q1 and 4 2 failures. service video tape supplement.
5326A/ B/ C/ 5327A/ B/ C-5 All serials. Field installation of
1310A COMPUTER GRAPHIC DISPLAY Option 011.
1310A-6 Serial prefix 1301A and below. Correction for 5326A/B/C/5327A/B/C-6All serials. Field installationof 8660B SYNTHESIZED SIGNAL GENERATOR
drive defocusing. Option 010. 8660B-8 Serials 1247A00320and below. 500 MHz
1310A-7 Serial prefix 1301A and below. Improved high 5326A/B/C/5327A/B/C-7 Allserials. Optionaladdition amplifier heatsink.
voltage power supply. of fuse to protect +I75 volt power supply. 8660B-9 Serial prefix 1247A and below. Improved
1310A-8 Serial prefix 1316A and below. Modification keyboard entry.
to reduce coupling between the Z-Axis input and 5340A MICROWAVE FREQUENCY COUNTER 8660B-10 Serials 1247A00300 and below. Improved
the X/Y inputs. 5340A-I Serial number 1252A00269and below. 3M cable, 14 pin connector.
Modification to eliminate oscillation on Hi-Z input. 8660B-11 Serials 1312A00401 and below. Digital
5340A-2 Serial number 1320A00450 and below. control unit mechanical checks.
1311A COMPUTER GRAPHIC DISPLAY
1311A-6 Serial prefix 1238A and below. Correction for Modification to improve chassis vibration stability.
drive defocusing. 5340A-3 All serials. Troubleshooting and checkout 8690 SERIES SWEEP OSCILLATORS
1311A-7 Serial prefix 1238A and below. Improved high information for H P interface bus (Opt. 003). 8690A-12A All serials. Replacement of capacitors
voltage power supply. 5340A-4 All serials. Mixer assembly AI 1 calibration containing PCB.
1311A-8 Serial prefix 1316A and below. Modification after AI 1U1 replacement.
to reduce coupling between the Z-Axis input and the 8 6 2 0 SERIES R F PLUG-INS FOR 8620AIB
X/Yinputs. 5360A COMPUTING COUNTER 86242A-1 All serial numbers. YIG oscillator
5360A-6 AU serials. List of parts in the 5360A replacement assemblies.
1402A DUAL TRACE AMPLIFIER Computing Counter service kit, H P part number 86250A/B-l All serial numbers. YIG oscillator
1402A-9 Serials prefixed 716 and below. Preferred 10636A. replacement assemblies.
replacement for Q302. 5360A-7 Serials below 1240A01076. New pana plex
display for improved reliability.
11661A EXTENSION MODULE
1405A DUAL TRACE AMPLIFIER I1661A-3 All serials. Installation checks and
1405A-2 Serials prefixed 450 and below. Preferred 8410A NETWORK ANALYZER
8410A-6 Serials 93501131 through 1144A02227. New adjustments.
replacement for 4404.
replacement hardware for mounting fan.
8410A-7 Serials 1310A02411 and below. Modification 86300 SERIES R F MODULES FOR 8620A,B
1415A TIME DOMAIN REFLECTOMETER to eliminate inherent cross-talk problems associated 86342A-1 All serials. YIG oscillator replacement
1415A-11 (Option 014 and Option H08) Time Domain with the rear panel outputs. assemblies.
Reflectometer preferred parts replacement. 86350A-2 All serials. YIG oscillator replacement
1420A-6 Serials prefixed 014 and below. Preferred 8605 COMMUNICATIONS SWEEP OSCILLATOR assemblies.
replacement for QlOl. 8605A-1 Serial number 1317A00210 and below. 86351A-1 All serials. YIG oscillator replacement
Improved operational amplifiers for A2 and A3 assemblies.
1815A/B TDR/SAMPLER driver assemblies. 86352A-1 All serials. YIG oscillator replacement
1815AIB-4 Serial prefix 1130A and below; 1815B Serial 8605A-2 Serial number 1317A00220 and below. Power assemblies.
prefix 1139A and below. Improved 1106A tunnel line filter capacitor change for 230 volt operation.
diode mount reliability. 86052-1 Serial number 1317A00230 and below. 86320/86330 MODULES
Improved operational amplifiers for A2 and A3 86330A-4 Serial prefix 1142A and below. Modification
1920A PULSE GENERATOR OUTPUT AMPLIFIER driver assemblies. to 86330A and 86331A for compatibility with
1920A-2 Serials prefixed 1211A and below. Preferred 8700A.
replacement for A2Q14, Q15, Q31, 432. 8620 SERIES SWEEP OSCILLATORS 86331A-2 Serial prefix 1142A and below. Modification
8620A-2A Serial prefix 1102A and below. Modification to 86330A and 86331A for compatibility with 8700A.
to reduce residual FM.
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ORDER FORM
COMPANY NAME
Please print your name and address clearly.
This will be used a s a shipping label. ADDRESS
0 Check here to receive a qualification form for CITY
a free subscription to Bench Briefs.
0 Check here to receive a free catalog
listing all H-P video tapes.
I STATE ZIP
Please check below the numbers of any desired service notes:
0 M-51 0 1310A-8 0 5216A-2 0 534OA-1 0 8640A-5/86408-6. 0 86608-10
0 136A-2 0 1311A-6 0 5300A-2 0 5340A-2 0 8640A-6186408-7. 0 86608-11
0 1150A-1 0 1311A-7 0 5300A-1A 0 5340A-3 0 8640A-7186408-8. 0 8690A-12A
0 1311A-8 0 534OA-4 0 864OA-8186408-9.
0 1208AlH11-2 0 5303A-1 0 86242A-1
0 5360A-6 0 8640A-9186408-10.
0 1208AlH11-3 0 1402A-9 0 5310A-1 0 8625OAlB-1
0 5360A-7 0 8640A-10186408-11.
0 1300AlH82-1 0 1405A-2 0 5326AlBlCl 0 8640A-11186408-12. 0 11661A-3
0 8410A-6
0 1308A-5 0 1415A-11 5327AlBlC-4 0 8640A-12. 0 86342A-1
0 1308A-6 0 8410A-7
0 1420A-6 0 5326AlBlCl 0 8654A-1 0 86350A-2
0 1309A-4 0 8605A-1 0 86351A-1
0 1815AlB-4 5327AlBlC-5 0 8660A-13
0 1309A-5 0 8605A-2 0 86352A-1
0 1920A-2 0 5326AlBlCl 0 86052-1 0 8660A-14
0 130949-6 0 8633OA-4
5327AlBlC-6 0 86608-8
0 1310A-6 0 3330A-3 0 8620A-2A 0 86331A-2
0 33308-3 0 5326AlBlCl 0 86608-9
0 1310A-7 5327AlBlC-7
0 3459A-11
0 Check here if you did n o t receive n copy of the complete
Service Note Index which wns published in April 1973. We will send you n copy.
Would you take a moment to answer a few questions?
Hewlett-Packard is always interested in improving the usefulness of operating and service manuals.
One area that has attracted some interest is microfiche. This is a method of putting an entire service manual on several
4 by 6-inch cards. These are then used with a viewing machine to retrieve the information. Thus the amount of storage
space needed for manuals is greatly reduced: in fact, many times the documentation for an instrument can be stored
in a small pocket inside the instrument.
We would like your opinion about microfiche.
1. Approximately how many file cabinet drawers [or equivalent space) are filled with HP service manuals at your facility? -
2. Have you ever used a microfiche viewer? a y e s U n o If yes, could you also answer questions 3 thru 8?
3. What w a s your reaction to this method of retrieving data in the manual?
O e x t r e m e l y good Ogood u n o reaction Obad n e x t r e m e l y bad
4. Do you regularly use a microfiche viewer? nyes u n o If yes, do you know what reduction ratio was incorporated
in the microfiche you n o w use [check all applicable reduction).
020 to 1 0 4 2 to 1 nother
0 24 to 1 0 4 8 to 1
5. Would you be interested in receiving future H P service manuals on microfiche?
O d e f i n i t e l y yes Operhaps nuncertain U p r o b a b l y not Odefinitely not
6. What advantages of microfiche do you feel are important to you?
7. What disadvantages do you see?
8 . Any other comments?
Thanks for your help
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SAFETY TIPS/QUIZ SOLUTION IWI
SHORT QUIZ
SOLUTION
The last issue presented a cube of
42 ohm resistors and asked for the
equivalent resistance between
points A and B. Also how much
voltage can be placed between A
and B without exceeding '/4 watt in
any resistor?
This problem could be solved by
loop equations, but a much simpler
approach is to recognize that R5,
R12, R10 and R14 are in an equi-
potential plane since the cube could
be looked upon as an elaborate
balanced bridge.
Therefore, these four resistors can
be replaced with an open or short
circuit with no change in circuit
performance. Thus the circuit sim-
plifies to this:
The experienced service person is cord. An ohmmeter connected from
always looking for ways to reduce the instrument chassis or case to
the repair time o n instruments. the ground pin on the plug should
Sometimes safety is compromised read less than 1.0 ohm. Flex the
in the process, unfortunately. cord a few times while making this
One of your primary concerns when measurement to detect any inter-
servicing or maintaining an instru- mittent break. A cord may look good
ment should be your safety and the and still be open or intermittent, so
safety of those who will use the be certain to check it thoroughly.
product following your work on it. 3. Instruments should be con-
It may be helpful for the novice as nected only to outlets that are
well as the veteran to review some properly connected to earth ground.
precautions which should be taken If a three-wire to two-wire adaptor
is used, be certain to connect the Substituting 42 ohms for each of
during the servicing of any electrical the resistors and simplifying yields
product. green wire to a good ground. Prod-
ucts have a third wire connected to this equivalent circuit.
1. Before removing covers, even if chassis to protect the operator in /& pleALf-&-L
you will need to make measure- the event of a short circuit in the f R/G+-B0
)-2ffi
A, -6
ments afterward, disconnect the instrument. Maintaining a good
power source. To rely on the in- earth ground connection will ensure
strument's power switch to discon- having this protection.
nect both sides of the line may get
you in trouble, especially on older Making measurements carefully, The equivalent resistance is
products. Even if the power switch deliberately and one at a time will
is double pole type, you still risk reduce the chance of an error or = 18 ohms
the consequences of dropping a accident. Taking a few extra sec- 126 + 21
cover, screw, or your hand on the onds to work safely is time well The watt rating of the resistors
power input terminals while disas- spent. means that any resistor can have a
sembling the instrument. maximum voltage across it of 3 . 2 4 ~
(sinceP=- ,substituting P=0.25and
E2
2. Before reconnecting the instru- Steve Fischer is the Product Safety R
ment to power for making your Officer at Hewlett-Packard in Palo Alto. R=42 yields E = I / W = 3.24).
measurements, it is a good practice Previously he was a Product Support But the equivalent circuit shows
(and should become routine) to Engineer at the Avondale, Pennsylvania two resistors in series in several
check the continuity of the third division. legs; therefore, the maximum volt-
wire ground if the product is Additional tips of this nature will be age allowed between Points A and
equipped with a three-wire power published in future issues. B is 6.48~.
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another dimension in
education and service
Product # Option # Count Any Signal 90030- 635
The proper AC-DC Switch, Attenuator
Choosing the Right AC Voltmeter 90030- 605 and level control settings for a frequency
Overview of the field of AC measurements counter for all types of signals. (10 min.)
identifying the proper AC voltmeter for
measuring AC current, etc. (22 rnin.) Time Interval Measurement 90030- 637
Review of the function known as Time
Improved Counter Measurements 90030- 72 1 Interval (T.I.) and how to select compatible
Instruction on how to find the total instruments. (I5 min.)
measurement error of a frequency
measurement, etc. (23 min.) Time Interval Averaging 90030- 633
A thorough program offering sound
Basic Electronic Counter Functions 90030- 534 practical advice on Time Interval
The seven basic counter functions best Averaging. (24 rnin.)
suited to a particular measurement need.
(17 min.) What Is A dB? 90030- 614
An explanation, with examples, of
The Reflectometer Calculator: 90030- 763 common conversions used in electronics.
Reflection Terms (16 min.)
A short, important rundown on how to use
the reflectometer calculator slide rule. Directional Coupler Introduction 90030- 578
(4 min.) An explanation of the terms used to
specify and describe couplers. (14 rnin.)
High Frequency Detectors and Terms 90030- 643
Identifies the four categories of high Digital Magnetic Tape Basics 90030- 50 1
frequency detectors. (10 min.) A summary of the applications for digital
mag tapes and comparison with other
Reflection Terms 90030- 636 storage media. (20 min.)
The four reflection terms used to describe
impedance at high frequencies. (15 rnin.) Time Domain Reflectometry 90060- 450
Basic theory of TDR measurements and
Source VSWR 90030- 71 1 major practical considerations in using the
A comprehensive discussion of Source technique. (31 min.)
VSWR at a termination level. (10 rnin.)
High-Reliability Component Terms 90030- 722
Power Measurements: Types of Systems 90030- 645 Terminology associated with HI-REL
Choosing the right method to measure high devices. (13 min.)
frequency power. (13 rnin.)
Logic Symbology 90030- 489
Transmission Lines 90030- 593 Clarification of the majority of HP-used
An explanation of transmission line terms logic symbols and an explanation of the
and functions. (14 min.) functions of the devices themselves. (20 rnin.)
The Smith Chart 90030- 642 S-Parameter Design Techniques 90060- 586
Explanation of the Smith Chart and its Part 1 of 2 presents a thorough review of
use. (29 min.) microwave theory. (54 rnin.)
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VlDEOTAPES 11 * I
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S-Parameter Design Techniques 90060- 600 Digital Building Blocks 90030- 783
Part 2 describes the characteristics of Characteristics of gates and flip-flops and
HP's 12 GHz transistor including its their applications. (18 rnin.)
S-Parameters. (56 rnin.)
Functional Analysis 90030- 785
Troubleshooting Transistor Circuits Faster 90030- 683 The basic functional building blocks of
A valuable collection of proven trouble- digital design and comprehensive coverage
shooting techniques. (17 min.) of algorithms. (22 min.)
Troubleshoot FET Circuits Faster 90030- 727 Electrical Analysis 90030- 786
Describes the various types of FETs Covers the specialized triggering require-
encountered in electronics equipment and ments and noise problems unique to digital
discusses basic FET theory. (16 min.) systems. (20 min.)
Numbering Systems and Digital Devices 90030- 784 Data Communications 90030- 787
An examination of the binary numbering Discusses basic data communications
system to aid in conversion of numerical terminology, component parts of a basic
data to and from decimal, binary, octal, communications network, and measure-
BCD, etc. (25 min.) ment problems. (29 min.)
Product # Option #
183A Oscilloscope Mainframe Adjustments 90030- 503 432A Power Meter Maintenance 298
Calibration procedures for 183A/ B (25 rnin.) Block diagram explanation of 432A
followed by maintenance and adjustment
1700 Series Service-Part 1 90030- 673 procedures. (60 min.)
Review of controls and assemblies on
Model 1700A (14 rnin.) 841OA/MllA Network Analyzer Service 90030- 490
Theory of operation of 8410A/8411A
1700 Series Service-Part 2 90030- 674 followed by phase-lock loop and sampler
Block diagrams and schematics of DC-DC troubleshooting techniques. (23 rnin.)
converter power supply and logic-controlled
trigger circuit. (20 min.) 8660 Series Signal Generator Service: Part 1 90030- 566
8660A/ B family block diagram discussion
CRT Service and Troubleshooting 90030- 704 followed by explanation of the function of
Review of cathode ray tubes: their connectors, controls, light indicators &
construction, adjustments and trouble- internal assemblies. (23 rnin.)
shooting techniques. (18 min.)
5061A Cesium Beam Tube Replacement 90030- 664
Understanding HP Storage Scopes-Theory 90030- 449 Replacement of cesium beam tubes &
Theory and operation of mesh-storage alignment. (30 min.)
cathode ray tube, plus use of operating
modes of storage oscilloscopes. (29 min.) 5360A Computing Counter Maintenance 90030- 513
Troubleshooting procedures for 5360A and
Understanding HP Storage Scopes-Service 90060- 359 Board Exchange Service Kit use. (27 rnin.)
Storage CRTs: common failures;
troubleshooting techniques, minor repairs, 5500A Replacing the Laser Tube: Service 90030- 456
etc. (37 min.) Alignment and calibration of 5500A Laser
Interferometer plus proper operation,
8064A Spectrum Analyzer Service 90060- 632 troubleshooting and replacement of the
How to localize problems with the 8064A laser tube. (24 min.)
to the board level to utilize board exchange
program. (35 min.) 8050A Spectrum Analyzer Maintenance 90030- 616
Do-it-yourself maintenance of the 8050A.
746A Maintenance 90030- 408 (20 min.)
746 A High Voltage Amplifier: Operational
theory and block diagramming, high 8064A Spectrum Analyzer Recalibration 90060- 663
voltage danger areas. Correct techniques Step-by-step recalibration of the 8064A.
for replacing boards & tubes. (28 rnin.) (35 min.)
3490A Multimeter Self-Test Troubleshooting 90030- 705 5050A/B Digital Recorder Maintenance 900601 300
Use of self-test feature of 3490A Maintenance procedures for the printer
Multimeter. (22 min.) mechanism section of the 5050A/ B. (43 rnin.)
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MORE ON dB AND using the technique to obtain an
approximation for these situations.
dBm WITHOUT LOGS As many readers pointed out, any
number can be calculated with
Many readers commented on the combinations of 10 and 3. Forexam- in a future issue. These let
article in the May/June issue about ple, 8dB is 10dB + 10dB - 3dB -
determining power ratios from dB 3dB - 3dB - 3dB, or a power ratio
without the use of logarithms of 10 x 10 x x x x or 6.25.
(page 4). It should also be pointed out that
The article states that not all num- this method introduces a very small
bers can be calculated with this error because 3dB is not exactly a
method and it goes on to suggest ratio of 2 to 1.
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