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CATALOG 22-A 1955




HEWLETT- PACKARD COMPANY 275 PAGE MILL ROAD, PAL0 ALTO, CALIFORNIA, U. S. A.
Oscillators-.008 cps to 10 MC
I Instrument I Primary Uses I Frequency Range I output I Price I Paae I




Instrument Primary Uses Frequency Range Voltage Range Input Impedance Price Page

-hp- 400AB
General purpose ac 0.003 to 300 v
measurements I O cps to 600 KC I I ranges 10 fifif shunt
25 megohms s200.00 36

-hp- 400D Wide range ac measurements 0.001 to 300 v I O megohms
High sensitivity IO cps to 4 MC 12 ranges 15 fifif shunt 225.00 32, 33

-hp- 410B Audio, rf, VHF maarurementr;
dc voltages: resistances 20 cps to 700 M C
0.1 to 300 v
7 ranges
I O megohms
1.5 @pfshunt 245.00 34, 35

f


Frequency Measuring, Monitoring Equipment




Channels 2 to 83
@ INDEX BY INSTRUMENT TYPE AND F U N C T I O N @
Instrument Frequency Range Characterlrticr Price Page
Output 0.1 b v to I v into 50 ohm load.
-hp- bO8C I O to 480 M C Pulse or C W modulation $ 950.00 66, 67
Direct calibration.
Output 0.1 p v to 0.5 v. Incidental 1,050.00 66,67
-hp- 608D IO to 420 MC FM 0.002 entira ranqe.
Output 0.1 pv to 0.5 v into 50 ohm load.
-hp- 612A 450 to 1,200 M C Pulse, C W or square wave modulation. 1,200.00 68,69
Direct calibration.
Output 0.1 pv to 0.223 v into 50 ohm load.
-hp- 614A 800 to 2,100 M C Pulse, C W or FM modulation. 1,950.00 70, 71
Direct calibration.
Output 0.1 p v to 0.223 v into 50 ohm load.
-hp- 616A 1,800 to 4,000 M C Pulse, C W or FM modulation. 1,950.00 70,71
Direct calibration.
Output 0.1 pv to 0.223 v into 52 ohm load.
-hp- 6188 3,800to 7,600M C Pulse, CW, FM or square wave modulation. 2,250.00 72, 73
Direct callbratian.
Output 0.1 pv to 0.071 v into 50 ohm load.
-hp- 620A 7,000 to I 1,000 M C Pulse FM or square wave modulation. 2,250.00 72, 73
Separate dower meter and wave meter section.
Output 70 pv to 0.223 v into 50 ohm load.
-hp- 6238 5,925 to 7,725 M C FM or square wave modulation. 1,750.00 74,75
Separate power meter and wave meter section.
Output 3.0 pv to 0.223 v into 50 ohm load.
-hp. 624C 8,500 to 10,000 M C Pulse, FM or square wave modulatlon. 2,265.00A 74, 7 5
Separate power meter and wave meter section.



Automatic, adjustable sweep,
-hp- 670HM 7 to I O KMC full "H" band coverage, high output, 850.00 76t77
varied modulatlon. with motor



Square Wave and Pulse Generators
Instrument Primary Uses Frequency Range Characterlstics Price Page

-hp- 21 I A Square wave generator I cps to I M C Output 7 5 v across 75 ohms or
. $265.00 24
60 v across 600 ohms
-hp- 212A Pulse generator -
50 5,000 PPS.
.02 psec rise time
Pulse length 0.07 to IO p c c , output
50 v to 50 ohm load 565.0015. 22, 23




*f.o.b. Palo Alto, Calif. Quantity discount quotations available from the factory.
Distortion, Wave Form Analyzers-20 cps to 20 KC
Instrument Primary Uses Frequency Range Characteristics Price Page

-hp- 300A Wave form analyzer 30 cps to 16 KC Variable selectivity;
measuring range I mv to 500 v $625.00 2427

-hp- 3308 Measures total audio 20 cps to 20 KC
distortion Includes input amplifier, VTVM 4IO.OOA 28, 29
-hp- 330C For FM broadcast 20 cps to 20 KC Special VU meter t o meet
measurements F.C.C. requirements 4 OO A
4.O 29

-hp- 330D For AM, FM broadcast 20 cps to 20 KC
measurements AM detector and VU meter to
meet F.C.C. requirements 455.00A 29




t For use with bolometer or crystal t For use with bolometer only 'Complete assembly including carriage f Mounts in 8098 carriage-See next page.


Microwave T e d Inskumen+s -for coaxial and waveauide svs+ems




A Rack mounted instrument available for $15.00 less. Copyright 1955 Hewlett-Packard CO.-Printed in U.SA.-3100 - 2.55 -50M
Rack mounted instrument available for $25.00 less.
Registered Trademark of the Hewlett-Packard Company.
Data subject t o change w i t h o u t notice. Prices f.0.b. f a c t o r y .



I.
ELECTRONIC

@ ASU NG STRUMENTS




Where to find the -hp- instruments
you need in this catalog

By instrument type or function:
All -hp- instruments shown in this catalog are indexed by type or function
on the tables beginning on page at left. (Example-`"Vacuum T u b e
Voltmeters." )

By instrument name or title:
All -hp- instruments shown in this catalog are indexed by name or title
at the back of the catalog. (Examples-"Amplifier" ;"Audio Oscillator.")

By instrument model number:
-hp- instruments are also listed numerically (by model number) at the back
of this catalog. (Example--"-hp- 410B Vacuum T u b e Voltmeter.")

Ordering Information:
Essential ordering information, terms and shipping and repair data are
listed on the following page.

Prices:
Prices of major -hp- instruments are listed in tables beginning on the page
to the left. Prices of certain small components and accessories are listed
on pages where such equipment is catalogued.

Warranty:
All -hp- instruments are warranted free from defects in materials and
workmanship. For details see page 119.

-
List of -hp- engineer salesmen:
-hp- engineer-salesmen are located in most major manufacturing centers
in the United States and Canada. T h e y are listed on the back cover of
this catalog. In addition, Hewlett-Packard is represented in many coun-
tries overseas. Names and addresses of representatives supplied on request.
ELECTRONIC

@ ASU NG STRUMENTS




Suggestions for Ordering

.
Order by Model Number . , Always order by Sales Representatives . . . Sales representatives
catalog model number and name of instrument de- are maintained in principal cities as a service to our
sired. For example, "Model 400D Vacuum T u b e customers. Customers are invited to contact the near-
Voltmeter." Whenever possible mention frequency est representatives a t any time. T h e y will gladly
range or other significant specifications to prevent supply technical information, help prepare your
misunderstanding. Also mention features such as order and, if desired, forward order to the factory.
special color, frequency range, non-standard power Orders should be made out to the Hewlett-Packard
line voltage, etc., and whether cabinet or rack mount- Company and are subject to final acceptance by the
ing style is desired. Company in Palo Alto. Sales representatives and
their addresses are shown on the back cover.
Most Hewlett-Packard instruments are available
in either cabinet or rack mounting. T h e letter "R"
after the model number indicates rack mounting. For .
Repairs . . W h e n returning instruments for re-
example, "400DR." An additional charge is made for pairs, recalibration, or any other reason, please con-
most rack mounting style instruments. tact the Hewlett-Packard Company for shipping in-
structions. Give model number, type number, and
Orders should be sent direct to the factory and serial number and as much information as possible
addressed to Hewlett-Packard Company, 275 Page concerning reason for return.
Mill Road, Palo Alto, California. All orders are
subject to final acceptance by the Hewlett-Packard Repairs are made by the Hewlett-Packard Com-
Company. pany at cost of labor and materials plus a small serv-
ice charge. Customers are invited to make full use
of this service to insure maximum benefit from their
Shipments ... Unless specifically requested other- instruments. I n most cases instrument repairs can be
wise, shipments are made by express or by truck, made locally at field repair stations maintained by
whichever is cheaper and more serviceable to the cus- our representatives in Boston, Chicago, Dallas, De-
tomer. Small items will be forwarded by parcel post. troit, Los Angeles, New York, Philadelphia, Syra-
W e do not recommend rail freight shipment. For cuse and Washington, D. C.
expedited service, we will gladly ship by air freight,
air express (more expensive), or air parcel post upon
Repair Parts . . . W h e n ordering repair parts
request.
please describe carefully parts required. Give model
number, type number, serial number of the instru-
Terms , . . 30 days net. Unless credit has already ment and date of original purchase. Identify parts of
been established, shipments will be made c.0.d. All the wiring diagram if possible, giving date shown
prices are quoted f.0.b. Palo Alto. on the circuit wiring diagram.
I




I T h e Hewlett-Packard Company was founded
in 1939 in Palo Alto, California. Here, in a suburban community
30 miles south of San Francisco, next door to Stanford University,
Hewlett-Packard is squarely in the heart of the important northern
California electronics center.
T h e first H e w l e t t - P a c k a r d p r o d u c t was a new k i n d of in-
strument - a resistance capacity audio oscillator. Hewlett-Packard
pioneered the resistance capacity circuit which is now an accepted
standard for test oscillator design.
D u r i n g the past decade and a half, the Company has steadily
broadened the instrument line, and now over 250 basic test instru-
ments are manufactured. Among the more important types are audio
oscillators, vacuum tube voltmeters, noise and distortion analyzers,
signal generators, p o w e r meters, broadcast monitors, electronic
counters, and a complete coverage array of waveguide and coaxial
instrumentation for microwave work. T h e Company now occupies
a modern and well-equipped plant in south Palo Alto, situated on
an 8 - acre site and including 140,000 square feet of laboratory,
manufacturing and office space. Over 700 men and women are now
regularly employed, and approximately 100 field representatives
sell and service - h p - instruments in the United States, Canada and
overseas.
Behind every - h p - instrument is a basic philosophy governing
equipment design, manufacture, sales and service. T h i s philosophy
specifies that there shall be built into each - h p - instrument the
greatest possible usefulness, accuracy, convenience, dependability
and dollar value.
Consistently, Hewlett-Packard has gone to lengths to insure
that these standards are met. Every effort has been made to assemble
the best engineering staff possible. T h e Company has sought not
only men of skill and experience, but men with vision and daring
and a desire to better the best.




Ultra-modern design features new 44,000 square foot administra-
tion and laboratorv building at Hewlett-Packard's Palo Alto olant.
Like other -hp- piant buildings, new structure is sound a n i light
engineered and air conditioned. I t contains one of the most modern
and complete instrument development laboratories in the world.


1
Another cornerstone of the -hp- philosophy is insistence on the
most up-to-date manufacturing methods. T h i s means not only mod-
ern techniques, but modern machinery. Hewlett-Packard's manu-
facturing departments are equipped with the newest and finest
machinery obtainable for the job. Typical of this equipment is a




specialized turret press which punches many sizes of perforations
on instrument chassis with a single set-up. Other examples include
a heavy duty die casting machine for fast production of dial drive
housings and other stationary parts, a fully-equipped machine shop
for manufacture of precision mechanical parts, and a complete
plastic molding department to fabricate special components which
are either unobtainable elsewhere, or can be made more quickly
and economically at -hp-.
I n addition to the different types of commercial machinery, a
number of special devices developed by -hp- engineers are in daily
use. Some of these were developed to meet unusual manufacturing
problems ; others were "imagineered" to make some special part
better, faster, or at lower cost. T h e y include such ingeniously simple
units as the Lazy Susans, turntables mounting many resistor boards
in a convenient position f o r assembly. And they include develop-
ments which are precision machines in their own right, such as
the Kingman machine which stamps out terminal boards in gross
quanti ties.




T h e new -hp- laboratory provides engineers T h e ingenuity of -hp- engineers has produced T h e -hp- plant is equipped with the mosi
with the most ideal working conditions pos- many devices to speed and simplify manufac- modern manufacturing machinery avail.
sible. Note semi-private work benches, gen- turing, produce better instruments at less able for the job. Here is a heavy duty dic
erous aisle space, large number of power cost. T h i s precision lathe for winding re- casting machine for prpduction of h o w
outlets and individual power controls. sistors handles wire as fine as No. 42. ings, shields, dials and other cast parts.



2
T h e Hewlett-Packard production policy is also somewhat dift-
erent from that employed elsewhere. Instruments are manufactured
in 11 runs," and actual fabrication is preceded by careful planning
to insure that all parts are available and supplied as needed to keep
the runs progressing smoothly. As many as ten runs are normally


A t Palo Alto, home of Stanford Uni-
versity, -hp- is located in the heart of
the nation's new electronics center on
the San Francisco Peninsula. T h e
-hp- plant may be reached by South-
ern Pacific commuter train ( t o South
P a l o A l t o s t a t i o n ) , by Greyhound
bus, or auto on U. S. 101. San Fran-
cisco's International Airport is just
30 minutes drive.



in progress simultaneously, yet production schedules are kept
flexible to permit meeting special orders or unusual delivery
requirements involving substantial numbers of instruments.
I n sales and service, Hewlett-Packard makes a particular effort
to provide customers with every assistance that will make the use
of -hp- instruments more efficient and productive. Factory-trained
field engineering representatives provide prompt, on-the- job con-
sultation as well as operating and repair information. These men
are constantly supplied with the latest in technical data and meas-
urement technique, and are in almost daily contact with the plant
at Palo Alto. F o r one week of each year, the entire sales organi-
zation meets at Palo Alto for an extensive new - information and
retraining seminar which includes not only theory but actual "field
problem" measuring with - h p - instruments and allied equipment.
O n many additional occasions, - h p - representatives return to the
plant for special training or instruction on new instruments and
measuring methods.




Another unit typical of the modern ma- T h e Kingman Machine, above, is another I n electronics, special or unusual parts are
chinery in daily use at -hp- is this turret device born and built at -hp- to make possible often hard to find, or prohibitive in cost. T o
press, a precision e q u i p m e n t w h i c h faster manufacturing at lower cost. Named avoid this roadblock to progress, -hp- has its
punches many sizes of perforations on for the -hp- engineer who "imagineered" it, own plastics and molding shop, which turns
instrument chassis with a single setup. it mass-produces terminal boards. out knobs, escutcheons, Nylon gears, etc.



3
A n equally significant part of the annual instruction given - h p -
engineer representatives involves field servicing - h p - equipment.
T h i s is an important function of the modern - h p - service policy
described on a preceding page of this catalog.




Old and neus. Pictured at right are
two - h p audio oscillators-the ver!.
tirst i n s t r u m e n t ( l e i t ) a n d t h e
brand-ne\\ 1Iodel 200AB oscilla-
tor. T h e -hp- line no\\ includes 11
dcscendants oi the original oscil-
lator which was the first low cost
oscillator employing the resistance
capacity circuit.


I n addition to rigid standards of instrument quality, the best
engineering and manufacturing possible, and thorough field engi-
neering service, there is one more aspect of Hewlett-Packard which
deserves mention here.
T h r o u g h the years, there has come into being a definite atti-
tude on the part of - h p - people toward the development, manufac-
ture and service of - h p - instruments. T h i s attitude is best described
as a genuine and pervasive team spirit, a spirit of cooperation
coupled with a common desire to excel. - h p - people are proud of
the quality and the utility of the instruments they design, make and
sell. This spirit translates itself continuously into better engineering,
better manufacturing, and better service.
T h e net result to you is good instruments - the best possible,
with broadest applicability and the lowest price consistent with
quality. Dependable instruments that are not only the best dollar
value when purchased, but the best investment for the future. - h p -
instruments - the standard of the electronic test equipment field.




Frequently, members of the world-wide -hp- field organization return to Palo Alto t o
learn the newest developments in instruments and the latest in measuring technique. I n
addition, all return again to the -hp- plant for a week-long annual seminar devoted t o
the operation and application of -hp- instruments.


4
0
SCILLATORS are among the signed to operate over wide frequency cps and over 1 MC. T h e low frequency
most basic and useful of all ranges and to provide generous output limit is set by the ballast element.
electrical a n d electronic voltages. Others are designed for par- T h e thermal time-constant of the lamp
measuring instruments. T h e y provide ticular applications. (ballast element) is such that at lower
a convenient source of power or test T h e circuit of the -hp- R C oscillator frequencies, lamp resistance tends to
voltages for almost all measurements, is shown in Figure 1. I t is fundamen- change in accordance with the varia-
including frequency, gain, impedance, tally a two-stage amplifier having both tions in amplitude of the individual
distortion, etc. negative and positive feedback loops. cycles of operation. This results in se-
There are three primary types of T h e positive loop, which includes the vere distortion of the output wave-
oscillators. These may be defined as frequency - selective network, causes form. Therefore it is necessary to (1 )
( 1 ) Beat-Frequency, ( 2 ) Coil Con- the circuit to oscillate. T h e resonant use a ballast element having relatively
denser or LC and ( 3 ) Resistance Ca- frequency is given by the expression greater thermal inertia, or ( 2 ) oper-
pacity or RC oscillators. ate the lamp at a point where radia-
f -- T h i s expression shows tion from the lamp is low.
"-2 li RC.
Throughout the years, the RC os- that the frequency or tuning span can
cillator has become recognized as the be made as wide as the capacity varia- High Frequency Oscillators
most versatile, practical, dependable tion in a tuning capacitor. T h u s 1O:l T h e high frequency limit of the
and easiest to use of all oscillator frequency variations in a single sweep RC oscillator is determined by the
types. Hewlett-Packard pioneered and are easily obtained, and a number of plate loading on the second tube of
developed the RC oscillator, and is
today the leader and largest manufac-
turer of this superior type of instru-
ment. -he- R C oscillators are highly
-- 1
stable, have wide frequency range and - I w
provide o p e r a t i n g flexibility which 71
4 I OUT 'PUT
makes them useful for many different
kinds of measurements. T h e y are ex-
--
* - I ---
I
tremely simple to operate and require
no tedious re-setting or adjustment R2 742
d u r i n g operation. T h e y a r e light-
weight, easily portable, and compact
- RK


in size to occupy a minimum of bench
space. Dependability of operation is
assured by clean, simple circuitry and
painstaking construction from quality
components.
bands can be used by changing the the oscillator. T h e impedances of the
T h e s e many advantages may be pairs of resistances. T h e negative loop positive and negative feedback loops
compared with the low stability, con- employs a non-linear ballast resistance are in parallel and the combination is
stant need for adjustment, narrow R, (usually a lamp), which automat- in parallel with the plate feed resistor
frequency range, inflexibility. large ically adjusts its resistance to compen- for the tube. At high frequencies, the
size and considerable weight of other sate for variations in output amplitude. combination impedance becomes low
oscillator types. T h i s results in very flat frequency re- and reactive, thereby reducing the
T h e -he- series of oscillators in- sponse and low distortion over the en- gain of the circuit and introducing
cludes 13 separate instruments which tire range. I t , also, reduces distortion phase shift. As a result, the distortion
are essentially resistance-capacity os- and limits amplitude of oscillations, increases and the errors in calibration
cillators. Collectively, they operate insuring a constant and stable output become severe. T o cut down the plate
over the entire range (Figure 2). loading effect, the combination imped-
from 0.01 cps to 10 MC, covering the
audio, sub-sonic, ultra-sonic and low Low Frequency Oscillators ance is made as high as possible. This
rf regions. A number of these instru- -kp- RC oscillators have been de- is achieved partially by reducing the
ments are general-purpose types de- signed to generate frequencies below l capacity of the tuning condenser, and


5
r




partially by raising the gain of the of the transfer characteristics of the
second stage (through use of tubes tubes. By a suitable selection of tubes,
with higher transcond iictance values). distortion in -hp- oscillators is approxi- AUDIO OSCILLATOR


At higher freqwricies the reduction mately %. T h e very low distortion
of gain and negative feedback makes obtained is primarily third harmonic. Figure 4. Voltage Divider Circuit.
the oscillator more susceptible to drifts (Second harmonic distortion is mini-
or variations caused by tube aging and mized by adjusting the dc voltages on tory for most applications. Other val-
supply voltage changes. As a result it the tube electrodes so that second har- ues of resistance may be used to ob-
is common practice to operate the cir- monic distortion generated by one tain different voltage divisions but in
cuit from a regulated power supply. tube of the oscillator is partially can- all cases the sum of the divider resist-
Most -hp- oscillators use an output celled by the other tube's transfer ance must equal the rated load in com-
amplifier whose main function is to characteristics.) For applications rc- bination with the input impedance of
isolate the oscillating circuit from the quiring very low distortion, a selective the equipment under test.
"work" circuit. T h u s , change in the amplifier following the oscillator can
work circuit does not reflect back to Accuracy
be used.
the oscillator and alter its amplitude, "Overall accuracy'' as applied to a
Hum
frequency or distortion characteristics. variable-frequency oscillator is a gen-
However, a unique arrangement is H u m is defined as alternating cur- eral term including factors such as
used in the -hp- 200CD Wide Range rents appearing in the output of an inherent circuit stability, mxhanical
Oscillator where the output is taken oscillator as n result of power-fre- stability, resettability of the tuning
from push-pull cathode followers di- quency voltages, currents and fields. system, readability of the tuning dial.
rectly to the output transformer. T h e Causes of hum are stray electrostatic dial calibration, component aging,
cathode followers offer a very low im- and magnetic fields, alternating cur- power supply variations and tempera-
pedance source to the load and thus rent in tube filaments or heaters, and
ture changes. Some of these factors
provide effective isolation of the oscil- discrepancies in filtering of power
affect short time stability; others af-
lator section. supplies.
fect long time stability. T h e accuracy
1)
-0
DISTORTION A N D AMPLITUDE CHARACTERISTICS
age of the audio oscil- specification of within 2% usually
OF RESISTANCE.CAPACITY OSCILLATOR
given for RC oscillators includes all
g +z lator is reduced, the
2 +I hum voltage tends to of these factors. (Typical long time
and short time stability are shown in
9 --c + remain constant. A t
I-
l o w e r o u t p u t levels Figures 5 and 6.)
2
+ -1

this hum voltage be- Description of -hp- Oscillators
$ -2

-hp- 200 series Oscillators (see page

.
tive to the sine wave
Z
1.0
output voltage. T h i s 8 ) are designed for general-purpose
0 0.5 applications, such as checking per-
I
- I d undesirable condition
e
e o"?
0.1
can be remedied by
operating the RC os-
formance of audio amplifiers, broad-
cast transmitters and similar equip-
0 10 100 1WO lMM0 lowOD
cillator at or slightly ment, checking vibration and stability
a4 FREQUENCY I N C.P.S.
of mechanical systems, and as voltage
- RC Oscilla'tor.
sources for bridge measurements, etc.
able a t t e n u a t o r be- T h e output is sufficient to modulate
There are, in general, two types of tween the oscillator and the equip- signal generators a n d drive other
output circuitry used in -hp- oscillators nicnt driven. T h e "voltage divider" equipment requiring considcrable pow-
depending upon the desired results. For circuit shown i n Figurr 4 is satisfac. er. T h e usefulness of thcse oscillators
very low distortion, low frequency, and
low power output, RC coupled output
is used. For high power or where vari- w
able source impedance is required,
m
Z
transformer output is generally em- 0
a
ployed. m
w
oi
Distortion
Inherently, the RC oscillator is a
generator of low distortion voltages. I FREQUENCY I
Distortion depends upon the linearity Figure 3. Characteristics of Frequency Determining Network.



6
equipment. I t uses an internal modu-
lator which allows the generated fre-
quency to be modulated by a standard
telephone set, thus permitting voice
communication between the test point
and terminal. It also provides a single-
ended output and includes a large tun-
DAYS
ing dial that gives a high resolution
and a convenient arrangement f o r
Figure 5. Long-time Stability Curve of circuit using wire-wound resistors a n d
temperature compensation. standardizing calibration.
T h e latest of -hp- RC oscillators is
the Model 200T, a precision teleme-
1.
0 tering test oscillator. It was specifically
designed to provide the highest possi-
.7S
ble frequency stability in a commercial
"*
1 0

%
.:a
: wide range, audio oscillator. I t covers
i'
-I the frequency range from 250 cps to
25
100 KC. T h e band spread is arranged
, I 1 I I I
2
I I I I
1
1 to provide wide overlap so that the
HOURS
entire RDB spectrum for FM - FM
telemetering is covered without split-
Figure 6. Short-time Stability C u r v e of R C Oscillator.
ting a single telemetering channel. T h e
large, 6" diameter dial with many cal-
is greatly increased by their compact in low frequency work where much ibration points over 300' of arc, allows
size, light weight and easy portability. time is required for ordinary circuits precise and swift frequency selection.
-hp- 2001 is especially suitable for in- to stabilize. T h e instrument has a short warmup
terpolation work and for applications cycle of less than an hour ; a short term
-hp- 202B (page 13) is an RC type
where the frequency of oscillatioii stability of better than 0.02% * O S %
low frequency oscillator. Its applica-
must be known very accurately. f r o m 10