Precision E-200-C Series User Manual

THE
SERIES
E-200-C
SIGNAL-MARKING
GENERATOR
The
series E-200-C
Signal-Marking
Generator is a
thor-
oughly
modern
A.C.
operated
instrument. It is a
highly ac-
curate,
reliable
and
stable source
of
variable
frequency
standards
for
aH
general radio
frequency
alignment, adjust-
ment and
test problems,
including F.M.
and
T.V. applica-
tions.
Included
are
direct
facilities for audio
frequency tests
with a separate
400
cycle,
sine-wave
audio
oscillator.
The usual
Dynascan
high
standards
of materials
and
workmanship
have not
been spared
and
as will be
noted
from
the
following
important features,
our
engineers
have
embodied
every
technically
advanced
circuit and
opera-
tional feature
providing
for the
utmost in
accuracy,
utility
and
ease
of
manipulation.
May
we
call to
your
attention
that on
the pages immedi-
ately
preceding
will
be
found both
pictorial
illustrations
and
a
schematic
diagram
of
this highly
unusual Signal-
Marking
Generator.
Reference to
same
while reading
the
following
would
be
of valuable
assistance
in more
fully
understanding
the
operational
features
described.
1.
The
A.V.C.
Substitution
System.
Supplying
it
own A.V.C.
voltage
from a
directly
cal-
ibrated
network,
(V-15-see
schematic),
the
Series
E-200-C
eliminates
the
necessity
for
critical
Signal
Generator
and
receiver
control
settings
to keep
align-
ment
procedure
below
the A.V.C.
threshold.
This volt-
age
is
independently
adjusted
to
coincide
with
the
actual A.V.C.
voltage
developed
by
the
receiver
under
normal
average
conditions of
reception and
accordingly
assures
accurate
and
efficient
alignment
of all
tuned
circuits, as
described
in detail
on page
7
and
following.
2.
Eight Bands.
Provide
a
continuous
coverage
from
88 kilocycles
through
440
megacycles;
88
KC
through
110
MC
on
fundamentals.
Band
A:
(88-230
KC)
Band F:
(15-29
MC)
Band
B:
(220-600
KC)
Band G:
(29-55
MO
BandC:
(550-1700
KC)
Band H:
(55-110
MC)
BandD:
(1.60-5.0
MC)
Band
Hz:
(110-220
MO
BandE:
(5-15.5
MO
Band
Ha:
(220-440
MC)
Special
oscillator
design
produces
strong
harmonics
whereby
the very
high
frequency
ranges
(110-220
MC)
and
220-440
MO
are
generated
with
the same
high
order
of stability
and
accuracy as
the
original
band.
The
(110-220 MC)
band is
calibrated
directly
on the
dial as
band H.
The
(220-440
MC)
range
is read on
band H.
Bands "F",
"G"
and
"H"
are electrically
band
spread
enabling precise
settings
to
fractions of a
megacycle,
especially
useful
for video
I.F.
marking
in television
receivers.
Eight
bands, are
used
to
provide unusually
wide
band-spread
of
true
electrical
nature,
allowing easy
direct
reading
of the
dial,
in frequency,
to
440
MC.
An
eight position,
positive acting band selector
switch
provides
for
simple
selection
of
any desired
range.
3.
Accuracy
-
Constancy
of Calibration.
A
6AU6
(see
schematic)
in
the
"Unit-Oscillator"
construction
provides
shortest
possible
leads
between
oscillator
and
associated
circuits. All
components
in-
cluding
coils,
trimmers,
condensers,
socket,
tube,
re-
sistors,
etc.,
are
actually
mounted
right
onto
the
band
switch, as
illustrated
in
the
picture
on
the
front
cover.
High quality,
ceramic spaced
band
switch, silver
plated
8 witch contacts,
ceramic
suspended trimmers,
plus silver mica
±
1%
padder
condenser
and
SLF
tun-
ing
condenser
in addition
to the rugged
"Unit-Oscilla-
tor"
construction,
insures +
1%
Accuracy
on All Bands
under widely
varying
conditions,
'ffiis permits use of
Series E-200-C
for complete F.M.
receiver
alignment
as well as
for TV
marker and
other TV
applications.
See
page
(18).
4. The
Circuit
-
Frequency
Stability.
As will
be noted
from
inspection
of the
circuit
dia-
gram,
the Series E-200-C
uses a
miniature
6AU6
in a
highly stable
electron-coupled
oscillator
circuit, modu-
lated
in the output
buffer-amplifier
section by a separ-
ate
400
cycle,
sine-wave audio
oscillator. A dual
tube,
type
6U8,
which
consists
of
atriodeand
pentode
in
one
envelope is used as a
combined
audio
oscillator, amp-
lifier, and
cathode follower
output tube. By
accomp-
lishing
modulation
in the
amplifier section, rather than
the
more
usual
method of modulating
the oscillator di-
rectly, minimum
frequency
instability is assured
even
at high
modulation levels.
This thereby
permits the
Series
E-200-C
to provide
completely
variable modula-
tion control
from zero to
100%. In such
manner, the
comparative signal audibility, as
against
the
usual
30%
modulated
oscillator, is increased
by
over 300% (this
is especially
advantageous
when adjusting
receivers
badly out of
alignment),
without the need of
raising the
R.F.
signal
voltage
to
over-load
proportions.
Utilizing
a
non-interfering dual R.F.
output attenua-
tion system
(V-10,
V-ll
and
associated components)
the oscillator
frequency is
unaffected by
output
loads
or
R.F.
control
settings. The use
of
a COAXIAL
OUT-
PUT CABLE
provides
appropriate
connections for test
requirements.
A
type
5Y3 full-wave
rectifier forms the
foundation
of a heavy duty,
hum-free
D.C.
voltage sup-
ply.
A
four
point selector
switch provides, AT WILL,
automatic
selection of
4
types
of test signal
voltages.
1.
Unmodulated
R.F.,
commonly
referred to as
C.W.
2.
400
cycle
internally modulated R.F.
3.
Externally modulated R.F.
4.
400
cycle
sine-wave audio
output.
5. Large Full
Vision 6Vi"
Dial and
Vernier Scale
with
Twin Engraved
Plasticele
Hairline
Indicator.
An
engine
turned,
non-tarnishing,
permanent, anodized
finished,
14
gauge
aluminum
dial
with
deeply
etched
scales
and numerals
provides
almost seven
feet of
direct
easy
reading
scale
length.
A
smooth operating,
and more costly
ball-bearing
planetary
drive system
eliminates
string and
belt-drive
difficulties,
insuring
stability
in dial
settings.

Precision E-200-C Series Specifications

General

Brand	Precision
Model	E-200-C Series
Category	Portable Generator
Language	English