TELE-TECH & - AmericanRadioHistory.Com

hen:
2Xn,
l / 10Aì0 l
I
10.8ór = ( 360 / l m /
Mu 10'
w= - -- --
or a 200 -mile range and XI = 39°
ä.I0'
w = --
0
- = I.'00 rpm
The PRE' with :, I6 -sided mirror would he:
PRF =
mX (1500)(161 400
60 fill
E. Resolution. For ultimate realism,
it is desirable that the system
operate as efficiently as real radar,
not more nor less. In the matter of
resolution, one must of course
specify a particular radar. The
resolution in azimuth for radar is
said to vary from a fraction of a
degree to as much as 10 °. The resolution
in range of course depends
on many things such as pulse width,
range scale, the properties of the
cathode ray oscilloscope used, etc.
For example, on the 200 -mile scale
the resolution is not better than
'/2 mile. The resolution capabilities
of the pick -up device can be made
better than radar if care is observed
in the optical system. At
present, two spots 1/4 in. in diamter
whose near edges are separated
by 1/4 in. along a radial can be resolved
into two separate target
pulses by the "pick-up" device when
placed 10 ft. from the screen.
Azimuth resolution at present is
about 1 /2 °. What is as important as
equalling the capabilities of radar
in simulating it, is not surpassing
these capabilities. Adjustment to
any desired degree of resolution
can be accomplished on the pickup
device by merely replacing the
round aperture in the optical system
by two adjustable, mutually
perpendicular slits, one in the plane
of the multi -facet mirror rotation;
the other perpendicular to it.
The above figures are, of course,
average since resolution depends
on many factors, both in real radar
and in simulated radar as well.
Simulation of Additional Factors
A. Ground Clutter. Ground clutter
is simulated in this system simply
by projecting on the screen any
prescribed contour of light. This
contour is reproduced almost exact -
(Continued on page 192)
ENGINEERS,
Electronic & Mechanical
PHYSICISTS:
Top Grade Openings
At Melpar Leader in
Electronic Research & Development
Due to our continuing expansion program, a number of top grade
openings exist in our new laboratories suburban to Washington,
D. C. We urge you to consider the following:
1. At Melpar the engineer is not tied to a pre- arranged schedule of
advancement. Instead, promotion and advancement are based on
individual recognition, where skill and ability are the paramount
factors of determination.
2. Melpar has doubled in size every 18 months for the past 10 years.
New openings occur constantly. This enables the engineer to advance
to positions of increased responsibility as soon as he is ready.
3. Our unique "project team" basis of organization gives the engineer
an opportunity to participate in entire problems from conception
to completion of prototype, and thus experience the "over -all"
approach to engineering problems necessary to eventual directorship
responsibility.
4. Our new air -conditioned laboratories encompass over 285,000
square feet and offer complete facilities for creative research and
design. In addition to our central Model Shop, supplementary facilities,
personnel and test equipment are available for immediate use
within each project group.
5. The Northern Virginia Area, suburban to Washington, D. C., in
which Melpar is located, offers excellent living conditions, enjoys
the Nation's highest per capita income, fine homes and schools. Recreational,
cultural and educational facilities abound. Fully- accredited
graduate courses are offered at the Melpar laboratories and at 5
universities in the Area.
Top Grade Openings Exist in These Felds:
Network Theory Systems Evaluation Microwave Technique UHF, VHF,
or SHF Receivers Analog Computers Magnetic Tape Handling Digital
Computers Radar and Countermeasures Packaging Electronic Equipment
Pulse Circuitry Microwave Filters Flight Simulators Servomechanisms
Subminiaturization Electra- Mechanical Design Small Mechanisms Quality
Control and Test Engineering
Write for complete information. Qualified engineers and physicists
will be invited to visit Melpar at Company expense.
Write: Technical Personnel Representative
M E L PA R Incorporated
A Subsidiary of Westinghouse Air Brake Company
3090 Arlington Boulevard, Falls Church, Virginia
Positions also available at our laboratories in:
Cambridge, Mass., 99 First St.; Watertown, Mass., Il Galen St.
Tele -Tech & ELECTRONIC INDUSTRIES June 1956 For product information, use inquiry card on pages 209 -210
191