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Dec. 25, 1,9151
S, l, TQURSHOU
2,579,627
DEFLECTION SYSTEM
Filed June 22, 1950
2 SHEETS-_SHEET 1
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INVENTOR
Jzmeon [Íômáazz
Dec. 25, 1951
'
s. l. T'oURsHou
2,579,627
DEFLECTION SYSTEM "
Filed June 22, 195o
2 SHEETS-_SHEET 2
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lNvEN-roR
J'Imeozz I. .Tazztyäozz
Patented Dec. 25, 1951
2,579,627
-UNITED STATES
2,579,627
' »
DEFLECTION SYSTEM i
Simeon I. Tourshou, Philadelphia, Pa., assigner` to
Radio Corporation of America, a corporation
of Delaware
Application June 22, 1950, Serial No; 169,656'
16 Claims.
(Cl. 315-27) 'l
.
i
2
The present invention relates to cathode ray
beam denection systems and methods and more
¿It is another purpose of the present invention
to provide a new and improved method and ap
paratus for >controlling the deflection amplitude
of electromagnetic cathode ray beam deflection
particularly although not necessarily exclusively
to electromagnetic cathode ray beam deñection
circuits of the type employed in television sys
tems.
5
systems in such a Way as to maintain the deflec
tion wave -form substantially unañîected by
changes in amplitude.
'
More directly the present invention relates to
width control arrangements for electromagnetic
deflection circuits of the television variety and
finds particular advantageous application to tele
It is further an object of the present invention
to provide a novel width control sysetmv for tele
vision horizontal deiiection systems which is par
vision type deñection systems of the power re
covery, reaction scanning type. In this regard
the present invention is especially useful in con
nection with the direct drive type cathode ray
beam deñection system'shown and described in
ticularly applicable to the electromagnetic direct
drive reaction scanning type of deflection circuit.
` In order toA realize >the above objects and fea
tures of advantage the present invention contem
plates the use of controlled degeneration in the
another U. S. patent application Ser. No. 90,612,
Ventitled “Television Deflection Power Recovery
Circuit” by Simeon I. Tourshou, ñled April'30,
More particularly the present invention as ap
1949, issued as Patent No. 2,555,831 on June 5,
y1951. Its utility, however, is to be no way con
strued as limited to such direct drive deiiection
contemplates the use of a controlled degeneration
means in the screen grid circuit of the output
amplifler.- An enhanced and expanded range of
output stageof the cathode ray deíiection system.
plied to a pentode type deflection output amplifier
systems.
amplitude control is further provided by the
In virtually all cathode ray beam deflection
present invention through the use of a loss con
systems employed in the electrical art it is desir
trolling circuit associated With the output circuit
of the Ydeflection amplifier by properly combining
and coordinating the actions of the loss control
ling circuit> and ‘the controlled degeneration
able that some means be provided'for controlling
the amplitude of cathode ray beam deflection. It
is further desirable that the means used to con
trol the amplitude of deflection be of such a
nature as to not adversely aiîect the wave form of
means.
the dei‘iection signal deñning the cathode ray
beam movement.
In television cathode ray beam deflection sys
'tems such an amplitude control is usually referred
to as a width or height control. Since the hori
zontal beam deflection circuits of a television sys
tem operate at relatively high frequencies.' the
circuit constants of the horizontal deflection sys
tem are quite critical. Attempts to provide ver
satile amplitude control of horizontal deflection
circuits especially of the electromagnetic variety
have been met with serious problems. Foremost
of these problems is that of providing suñ'icient
amplitude control without encountering non
`linearity in the saw tooth wave form of current
deflection Wave form.
-
The present invention as particularly applied
to electromagnetic cathode ray deñection systems
employing screen grid type output tubes receiving
deflection signal drive from a multi-vibrator type
deflection signal source contemplates the use of
a novel and frequency stabilizing circuit. This
stabilizingvcircuit in accordance with the present
invention comprises a frequency control means
for the multivibrator which in turn is actuated or
0 controlledby the degeneration means of the out
put amplifier. In this way changes in deflection
amplitude have a negligible effect on the fre
quency'of the deflection signal.
In orderto more fully appreciate all the novel
features of the present invention in additionA to
passing through the deflectionyoke. This prob
lem of width control versus linearity in television
deflections systems is most prominent in elec
tromagnetic deñection systems of the direct drive
type wherein the electromagnetic deflection yoke
itself is placed directly in the anode cathode cir
50
cuit of the deflection output ampliñer.
klt is therefore a purpose of the present inven
those set'forth above, as well as obtain a more
complete understanding of its nature and oper
ation, reference may be made to the following
description taken in connection with the accom
panying drawings in which:
_ ,g
Fig. A.1- is a combination block and schematic
representation of one form of the present inven
tion to provide an improved amplitude control
arrangement for cathode ray beam deflection
systems.
A wide range of amplitude control is
made possible with negligible influence on the
` tion as applied to a television receiving circuit. _
55
Fig. 2 is a graphical representation of certain
aravaca?
3
4
Fig. 3 is a combination block and schematic
representation of another form of the present in
ondary winding 42 of this transformer are rec
tified by the high voltage diode 44 to produce
beam accelerating potential for the kinescope
second anode terminal 4B. The lower extremity
vention as applied to a television type deflection
circuit.
of the primary winding on transformer 40 is
then connected with the horizontal deflection
characteristics peculiar to the novel operation of
the present invention.
yoke winding 49 of the deflection yoke. From the
Fig. 4 is a further modiñcation of the present
invention as applied to a typical cathode ray
beam deflection circuit.
Turning now to the drawings there is shown in
Fig. 1 a television receiver section I0 adapted
lower end of the;deflection yoke winding a ca
pacitor 50 is connected to the upper end of the
variable linearity inductance 52.' The lower end
of _the inductance 52 is connected to the -l-B
to amplify and demodulate signals intercepted
by the antenna l2. The output of the television
receiver section l0 is made available at output
terminal I4 for application to the grid of the
Yimage reproducing kinescope shown at I6. >A
portion of the demodulated signal is also made"
,
available for the synchronization pulsev sepa
rator circuit I8. The separator circuit I8 de
livers vertical synchronizing information to the 20
vertical deiiection circuits 20. The separator
circuit I8 also provides synchronizing informa
tion to the horizontal deflection generator 22.
The output of the vertical deñection circuit 20
description and disclosure of this circuit and its
operation may be found in the RCA Service
Notes on Television Receiving Models T164,
TC1664’TC167, and TC168, iirst edition dated
March 10, 1950.
Briefly, the discharge tube 38 is biased by some
means so that under normal operating conditions
_ the tube 28 conducts only during the positive go
is indicated for. application to the terminals
Y-Y of the deiiection yoke 24 associated with
ing extremities of the saw-tooth 26. This bias
may be obtained through the use of a bleeder
resistor such as E6 connected between a source
the kinescope I5. The horizontal-dellection sig
nal generator 22 is by way of example illustrat
ed as being productive of saw tooth type deñec
tion drive wave form 2c generally found in tele
vision deflection circuits.
power >supply terminal at 54 and additional ca
pacitor 55 is connected from the lower end of
the winding 48 also to the positive power sup
ply terminal 54. Detailed description of the op
eration otthis circuit is described in the above
identified U. S. patent application. A further
of positive potential at terminal 58 and the up
30 per end of cathode resistor 34.
Such bias con
ditions cause a saw-tooth of current to start
Typicalk circuit arrangements suitable for ap
plication in the block diagram representations
building up in the yoke of the winding 48 dur
ing the latter portion of the saw-tooth 26. As
Ythus far discussed may beY found in an article
soon as the retrace portion of the saw-tooth oc
curs an `oscillatory ringing starts in the winding
43. This is damped by the diode 60 to cause a
saw-tooth of current to commence ñowing in
entitled “Television Receiver” by A. R. Wright, ‘
appearing in the March, 1947 issue of the RCA
Review.
Y
.
the yoke 48 in the opposite direction to that
produced by the peak of the saw-tooth 26. By
rangement in Fig. 1 is based primarily on the
.discharge tube 28. By way of example, this tube 40 properly adjusting the bias on the tube 28 and
the amplitude of the signal 26 a quite linear
has been shown as being of the screen grid va
saw-tooth of current suitable for deflection pur
riety. Thedeñection signal 26 is applied to the
poses may be produced through the winding 48.
.control grid 30 of the , output discharge tube.
The above operation _is predicated upon the sup
lThe cathode 32 of the Voutput tube is convention
-ally connected >with ground through the cathode i ply to the screen electrode S2 of a suitable pos
itive potential asl is required for conventional
fresistor 34. Resistor 34 is by-passed by capaci
screen grid type tube operation.
a
tor 36 so as to` reduce `degeneration in the cath
However, according to the embodiment of the
ode circuit.V By wayof example, the anode 38
present invention shown in Figure 1, the screen
of the discharge tube 28 is connected with .the
electrode 62 is connected to the +B source of
winding r11-œ of deflection yoke 24 rthrough a
positive potential at »terminal 54 through re
ydirect drive type deflection circuit employing B
sistances 64 and 66. According to the present
boost power recovery, reaction scanning action.
invention only the resistor 54 is completely by
The precise form of deflection circuit with which
passed. This is accomplished in part by capac
the output tube 28 is connected is not ofim
' - itor 58 and in part by the capacitor 10. In fur
Aportance to the successful V,operation of the pres
_. The -horizontal deflection ampliñer of the ar
ent invention, however, the direct drive type de
.ñection circuit has been illustrated since the
.problems overcome by the present invention are
perhaps most prominent in this type ofdeflec
ther accord withl the present invention the re
sistance tâis made variable. The time constant
of the resistor 64 with its associated capacity
should be such that when resistance tt is ad
’îwhich may be connected in the anode circuit of
justed to be zero the time constant in the screen
_circuit is substantially greater than the recur
tube 28 are shown and described in an article
rence frequency of the deñection wave form 26.
entitled “Television Deiiection Circuits” by A. W.
Furthermore, the capacitor ‘m is made large
enoughrso that when resistor @6 is made sub
tion circuit.
Other types of deflectioncircuits l
Friend appearing in the RCA Review for March,
l1947. Another article entitled “Magnetic De
'-'flection Circuits for Cathode Ray Tubes” by
AOtto H. Schade appearing in the RCA Review
L for September, 1947 describes even lanother typ
»ical magnetic deflection circuit to which the
present invention ñnds ready application.
stantially equal to zero the screen grid 62 is. eS
tablished at practically A. C. ground potential
at signal frequencies corresponding to thede
ñection wave form. That is to say, the capacitor
'I0 is made large enough to offer a very low im
pedances path to deflection signal components.
. Under such conditionskthat is with resistance 65
The direct drive deflection circuit shown in
equal to zero, the deflection circuit will oper
Figure 1 comprises a connection from the anode
ate- in va somewhat conventional manner and will
38 of discharge ltube 28 to the primary _of the
high voltage step` up transformer 40. »Deflec- . produce maximum deflection amplitude. Linear
tion fly-back pulses appearing across the sec 75 ity of the wave form under such conditionsinay
255.79’2627.
ä
be' adjusted by varying the value of A. induct
ance 52.
~
,
_
_»
According to the present invention, if it
should be desired to reduce the amplitude of de
flection wave form, the tap 'I2 on resistance Sti
is moved to the right so that both anìacceler
ating and a D. C. voltage drop will occur- across
the resistance GS.
Since resistance 60 is not
completely bypassed, this accelerating voltage
tube 28. As Well known by those familiarwith
deilection circuits, changing the eiîective drive
to a reaction scanning type circuit causes notice
able changes in the linearity of the resulting
deflection. In the present invention, however,
the effective control grid versus cathode voltage
iiuctuations or driveremains constant and hence
changes in the linearity of deflection current
are minimized.
.
,
drop will produce screen grid degeneration. The 10
In still further accordance with the present
eiïects of introducing screen grid degeneration
invention a greater range of amplitude control
in this manner may be illustrated by the graph
may be obtained yby carefully controlling _the
ical curve of Figure 2.
»
losses in the reaction scanning deflection circuit
The graph of Figure 2 shows a plot of screen
during the control of degeneration in the screen
current versus screen voltage of tube 28 for vari 15 grid circuit. Whereas prior art attempts> to
ous control grid-cathode voltages. Three such
control deflection amplitude byV adjusting losses
curves are shown'at i4, ‘i6 and i8, respectively.
in the reaction scanning circuit have been suc
Curve 'is depicts the screen current versus
cessful to a degree, the range of »such control
screen voitage characteristic for a control grid
has been limited by the resulting deflection wave
cathode potential of zero volts. Curve 'iS shows 20 form distortion when circuit losses were made
the characteristic for a control grid-cathode
too high. According to the present invention,
voltage equal to some nominal value E. Curve
‘I8 illustrates the screen characteristics of the
tube for a control grid-cathode voltage which
however, by properly introducing the correct
amount of degeneration in the screen grid circuit
it is possible to realize an increase in the amount
is sufficiently negative to establish cutoff in 25 that deflection amplitude may be usefully __re
the tube. Thisl value of voltage is indicated
duced by applying losses in the reaction scanning
as ENC referring to non-conduction in the tube.
circuit. This synchronized action of imposing
With the resistance 66 equal to zero virtually
circuit losses and degeneration may be accom
no A. C. impedance is imposed in the screen
plished by the convenient arrangement shown
grid circuit so that a deflection drive wave form 30 in Figure 1. Here the resistance 66 is a portion
such as 25, which is of suñìcient amplitude to
of potentiometer. The right hand end 02 >of
drive the control grid from zero volts to ENC,
the potentiometer may be connected through the
will produce a screen current variation which
switch 94 to resistance 96. The right hand ex
is indicated by the vertical distance between
tremity of resistance 06 is in turn connected to
points 80 and 82 on the ordinate of the graph
the upper end of inductance 52. Withl .the
_in Figure 2. This zero impedance condition as
switch 90 closed the inductance 52 is fully shunt
stated before, corresponds to the maximum
ed by a variable resistance whose value-may
deflection amplitude producible by the circuit
be adjusted by positioning the potentiometer
and may be referred to as maximum width. It
arm 16.
'
is, of course, understood that the vertical line 40
Operation of the present invention in this
86 corresponds to the average D. C. screen
regard is substantially as follows: As the arm
voltage. The difference between this average
16 is moved to the right in Figure l an increased
value and +B represents the D. C. voltage drop
amount of degeneration is imposed in the screen
across the resistor 64.
n
grid circuit. At the same time the inductance
Should now, still looking at Figure 2, the re
52 is shunted by a lower value of resistance. This
sistance 5t be given some ñnite value the screen
increases circuit losses in the reaction scanning
voltage ñuctuations will be defined by some load
system and, therefore, reduces the eiiiciency
line such as S6. The slope of the load line 86
thereof. This results in a reduced amplitude
will be made to correspond to the actual resist
of deflection. As pointed out above, the in
ance 50 as well known in the art of graphically
creased degeneration also produces a further
analyzing vacuum tube operating characteris 50 decrease in the amplitude of deflection.> This
tics. Under such conditions the same given
compound control is not aggregative in nature
amplitude of deñection drive by the wave form
since, as pointed out above, a wave form com_
2S will still produce a control grid voltage change
pensating inñuence is involved.
»
from zero to ENC. However, now the resulting
55 ' The embodiment of the present invention
screen grid current fluctuations will be much
shown in Figure 3 is in some aspects similar to
less than before and may be indicated by the
that shown in Figure l. The same type of direct
vertical distance between point 88 and 90 on
drive reaction scanning circuit is shown in FigureV
the ordinate of the graph in Figure 2. This
3 _as was'indicated in Figure l. Here, however,
has been arbitrarily indicated as being the screen
60 the output tube 98 has its screen velectrode ,|00
voltage variation corresponding to minimum
supplied with bias through- a somewhat diiîerent
width. Since plate current fluctuations are a
configuration of variable impedance from that
function of screen current changes in a -pen
shown in Figure l. Here the screen gridA |00 is
tode it is clear that changing the valueV of re
connected with +B potential at 54 through two
sistance 60 will produce similar changes in the 65 resistance paths. The ñrst path comprises re’
amplitude oi actual yoke deñection current.
sistance |08 in series with resistance | l2; The
It is of importance to note that although in
second path comprises resistance |02. With the
the prior art degeneration has been employed to
tap arm |04 of the potentiometer |06 moved to
control the amplitude of deiiection produced
the upper extremity of potentiometer resistance
by vacuum tubes nowhere in the prior art has 70 a minimum resistance is imposed in series with
controlled degeneration »been employed in the
the screen grid circuit. This resistance comprises
screen grid circuit of a -pentode The method
the parallel combination of resistance |08 and
of control provided bythe present invention is
advantageous since the degeneration imposed
resistance |02.` Capacitor ||0 is made sufficiently
large under these conditions'so as to heavily by
does not alter the effective drive to the discharge 75 .pass the resulting resistive impedance. ' Now, -as
*î
9579,62?
the tap |04 is lowered on the potentiometer |06
an unbypassed resistance | |2 comes into the pic
ture. This imposes degeneration in the circuit
and causes a reduction in deflection amplitude
as was the case in Figure l.
The arrangement in Figure 3 further differs
from that of Figure l in the following respect.
Figure 3 indicates that the pentode 98 is being
driven by a multivibrator type of sawtooth de
flection wave form generator. This generator is
of the time averaging type and is based on the
dual triode H4. The first section ||6 of the dual
triode ||4 operates as a timing comparator cir
cuit so as to compare the incoming signal from
the synchronizing pulse separator |8 with the
developed saw-tooth | |`|- appearing at terminal
||8. The resulting signal comparison produces a
control voltage at terminal |22 of the cathode cir
8
`circuit of tube 98 is increased as disclosed ‘bei
fore. This degeneration reduces the effectiveness
of screen grid |00 to shield the anode from the
control grid of the pentode 98. Due to the well
known Miller eifect this increases the effective
grid-to-cathode capacitance of the pentode 98.
Such an increase is effectively in shunt with the
saw-tooth charging capacitor associated with
blocking oscillator |26. The time constant of the
blocking oscillator will therefore be increased.
This will tend to reduce the frequency of the
blocking oscillator'. However, in accordance with
the present invention, the aforementioned move
ment of the tap |04 downwardly to increase de
generation has increased the potential applied
to the anode of triode ||6.
This will cause the
terminal |22 to become more positive and apply
a more positive bias to the grid of the blocking
oscillator triode |26. As well known by those
cuit of triode H6. Terminal |22 is' connected to
the grid |24 of the second triode section |26. 20 familiar with blocking oscillator action, this in
crease in positive bias wil-l tend to increase the
Triode |26 is further connected to operate as a
blocking oscillator type saw-tooth generator.
Thus, as the incoming synchronizing pulse signal
is compared in time with the resulting saw-tooth
appearing at terminals | |ß the bias on the triode
section |26 is established to provide the proper
operating frequency for the blocking oscillator
saw-tooth generator. The feed-back transformer
for the blocking oscillator is shown at |28. Its
primary |30 is connected in the anode circuit of 30
triode |26 while its secondary |32 is connected
in shunt with the grid circuit of the triode |26
through capacitor |34. Positive potential for the
anode of the triode |26 is supplied through the
resistance |36 connected with a source of -|-B
potential at terminal 54. The saw-tooth dis
charge capacitors |38 and |40 are connected with
frequency of the blocking oscillator and there
fore tend to compensate for the increased Miller
effect capacity imposed by the pentode 93. The
parallel resonant circuit |44 connected in series
with the anode circuit of the triode |26 acts as a
further stabilizing influence on the blocking os
cillator frequency as described in the above men
tioned U. S. patent application 136,021 and Radio
Television News article. The resonant circuit |44,
of course, forms no part of the present invention.
It is to be understood that the novel frequency
correcting action ofV the present invention is not
limited to the preferred form of signal generator
shown in Figure 3. For example, in Figure 4 a
very basic» type oí blocking oscillator saw-tooth
generator is indicated.. No means are provided
for time averaging frequency control of the block
the upper end of the resistor |36. The saw-tooth
ing oscillator by comparison of received syn
developed across these capacitors is applied to
the grid of the output’ tube 98 through a small 40 chronizing pulses with developed saw-tooth.
However, in Figure 4, the triode |46 due to the
resistor |4|.
action of the transformer |48 and grid time con
The particular form of time averaging saw
stant afforded by capacitor |52 and resistor |54
tooth deilection generator shown in VFigure 3 as a
sustains periodic blocking oscillator operation.
source. of driving signal for the output tube 98
Saw-'tooth capacitor |55` charges substantially
and is of the general type shown and described
linearly through changing resistor lee during
in U. S.` application 136,021 ñled December 30,
non-conduction of the blocking oscillator tube
1949, by Simeon I.v Tourshou entitled “Beam De
|46. During conduction of the tube |46, how
flection Control for Cathode Ray Devices.” A
ever, the capacitor |56 is discharged. This charg
full description and operation of this type of sig
nal deilection generator is also to be found in the 50 ing and discharge produces the conventional saw
tocth wave form shown at |60. Such a blocking
January, 1950, issue of the Radio and Television
oscillator saw-tooth generator is shown and de
News» in an article entitled “A Single Tube
scribed in the above article» “Television Deflec
A. F. C. Circuit for TVl Deflection Systems” by
tion Circuits” by A. W'. Friend appearing in the
John A. Cornell commencing on page 58. Ac
RCA Review' for March, 1947. As well known by
cording> to these> references the anode potential
those skilledk in the television art the frequency
of the» triodeI section 116' is made manually vari
of the blocking oscillator |46 is dependent upon
able’ by means of a potentiometer sucl-il as |42
the value of +B voltage applied to the circuit.
sothat a manual control of the deflection genera
The higher the +B voltage applied to the cir
torA frequency may be had. In such- applications
the right end extremity of the potentiometer |42 60 cuit the higher will be the anode voltage applied
to the triode |96. This Will cause- the tube |46 to
wasv connected with a ñxed source of positive B
potential. Thus, as the. value of theA anode poten
reiiect a higher mutual conductance which will
result in greater peak charging of the grid cir
tial ofthe triode H6 was changed the potential
appearing atv |22. changed and the bias on the
cuit It.< C. combination. This of course will de
blocking oscillator triode |86 wasA altered. This,
crease the effective> operating frequency of the
of course, caused a frequency change.
blocking oscillator.
AccordingY to the present invention the right
hand terminal of potentiometer |42- insteadY of
In accordance with the present invention the
output pentode> 99 in Figures. is connected sub
being` connectedv to a fixed source of positive po
stantially in the same manner shown in Figure 3
tential, it is connected to the4 lower extremity of
to provide variable screen grid degeneration con
trol. Thus, in Figure 4, as the tap> |04 is moved
downwardly on the potentiometer element |06,
the degeneration `in the screen-grid circuit of the
tube 98 is increased. As described above this
increases the effective*v Miller capacity-"in shunt
potentiometer |96- associated with the above de
scribed reaction scanning circuit. The `following
operation is obtained: When the degeneration
control tap |04 is moved' downwardly along poten
tiometer |~06§vthe degeneration inthe screengrid
‘2,579,627
" With'thesaw-tooth capacitor> i06- and lowers >the
frequency of the multi-vibrator. However, as the
tap |04 is moved downwardly on the potentiom
eter H36, the D. C. voltage drop across the re
sistance section H 2 becomes greater and the
anode voltage-applied to the blocking oscillator
triode is decreased. As indicated above, this
tends to increase the frequency of blocking os
cillator I 4S and hence compensate for the in
crease in Miller capacityproduced by increased
degeneration.
`
'
From the foregoing, it can be seen that the
applicant has provided a new and useful width
control arrangement for cathode ray beam de
l'nected in shunt with> at least a portion lof said
»reactance to form a time constant circuit, and
Vmeans for varying the value of said resistance
whereby to concomitantly vary the time con
stant of said time constant circuit as well as the
direct current potential reaching said intermed
‘ iate electrode.
4. >In an electromagnetic cathode ray deflection
>system employing a deñection yoke in combina
tion, a source of deflection signal having’a pre
determined period of recurrence, an output tube
having at least an anode, cathode control elec
trode and supplementary electrode interposed
between said anode and said control electrode,
flection systems. It will be appreciated that al -15 connections for applying the output of said de
though the present invention has been described
flection signal source to said control electrode,
in conjunction with electromagnetic type deiiec
an output circuit connected between said anode
tion systems, its principle can be applied with
and said cathode, said output circuit including
advantage to electrostatic type deflection sys
means for coupling electrical variations developed
tems as well. Moreover, the novel frequency 20 therein to the deflection yoke, a source oi’ posi
correcting action of the present invention, as
tive biasing potential having its negative’ ter'
shown herein, although illustrated in connection
minal connected with said output tube cathode,
with blocking oscillator type saw-tooth deflec
a variable resistance connected between said‘sup'
tion circuits, may be, of course, applied to other
plementary electrode and the positive terminal
types of deflection signal sources whose frequency -25 of said biasing potential source said resistance
of operation may be controlled by altering cir
being variable between a high and low limitgîa
cuit operating potentials.
capacitor connected in shunt with at least a por
What is claimed is:
tion of said resistance to form a time constant
1. In an electromagnetic cathode ray deflec
circuit the value of said capacitor being~ such
tion system employing a deñection yoke in com 30 that the'time constant value of said time- con
bination, a source of deflection signal, an output
stant circuit is not substantially greater lthan the
tube having at least an anode, cathode control
recurrence period of said deflecting signal when
electrode and supplementary electrode interposed
said variable resistance is at its high limit. ï ' »
between said anode and said control electrode,
5. Apparatus according to claim '4 wherein
connections for applying the output of said de 35 said output tube is of the pentode variety and
ñection signal source to said control electrode, an
wherein said supplementary electrode is the
output circuit connected between said anode and
screen electrode of said pentode.
‘
said cathode, said output circuit including means
6. In an electromagnetic cathode ray deilec
for coupling electrical variations developed there
tion system employing a deilection- yoke in com.
lin to the deflection yoke, a source of positive 40 bination, a source of deflection signal having'a
biasing potential havingk its negative terminal
predetermined frequency, an output tube having
connected with said output tube cathode, an im
at least an anode, cathode controlelectrode and
pedance having a resistive component connected
supplementary electrode interposed between> said
between said supplementary electrode and the
anode and said control electrode, connections for
positive circuit of said biasing potential source '
applying the output of said deflection signal
whereby to introduce degeneration in the de 45 source to said control electrode, an output cir
flection system, a capacitor connected in shunt
cuit connected between said anode and said
with at least a portion of said impedance to form
cathode, said output circuit including means'for
a time constant combination, and means> for
coupling electrical variations developed therein
varying the value of the time constant of said
to the deflection yoke, a source of positive bias
50
time constant combination such as to control
ing potential having its negative terminal con'
the amount or” degeneration present in said -sys
nected with said output tub'e cathode, a resistance
tem.
connected between said supplementary electrode
2. Apparatus according to claim 1 wherein said
and the positive terminal of said bias source to
discharge tube is of the pentode variety and
form a supplementary electrode circuit, a ca
wherein said iirst and second control electrodes
pacitor connected in shunt with at least a por-.
are respectively the control grid and screen grid
tion of said resistance, the value of said capacitor
of said pentode.
v
being so related to the deñection signal frequency
3. In an electromagnetic cathode ray deflec
and the Value of the resistance across which it
tion system employing a deflection yoke in com
is shunt connected that a degree of degeneration
bination, a source of deflection signal, an out
is produced in the supplementary electrode cir-'
put tube having at least an anode, cathode con
cuit, and means for concomitantly varying both
trol electrcde and supplementary electrode in
the degree of supplementary electrode circuit- dez-r`
terposed between said anode and said control
generation so produced along with the value ‘of
electrode, connections for applying the output of
potential applied to said supplementary electrode~
said deflection signal source to said control elec 65
'7. In an electromagnetic cathode ray defiecf
trode, an output circuit connected between said
tion system employing al deflection yoke in com
anode and said cathode, said output circuit in
bination, a source of deflection signaL'an output
cluding means for coupling electrical variations
tube having at least anranode, cathode control
developed therein to the deflection yoke, a source '
electrode and supplementary electrode interposed
of positive biasing potential having its negative 70
between said anode and said control electrode,
terminal connected with said output tube cath
connections for applying the output of said de
ode, a reactance connected between said supple
iiection signal source to said control'electrode”,
mentary electrode and the positive terminal or”
an output circuit connected betweenrsaid> anode
said biasing potential source, a capacitor "con
and said cathode, said output circuit including
antrace?
ll
12
~`means for coupling electrical variations developed
»minal connected with said output tube cathode,
third the value of said resistance means whereby
to obtain versatile control of the amplitude .of
deflection signal applied to said deñection yoke.
1l. Apparatus according to claim 10 wherein
means for applying said positive bias source to
said source of de?leotion signal comprises a self
therein to the deflection yoke, a source of posi
tive biasing potential having its negative ter
excited multivibrator circuit having as part of
said supplementary electrode, means to produce
its output circuit a sawtooth discharge capacitor
degeneration in said output tube, and means for
where value deñnes in part the frequency of said
concomitantly varying both the value of bias po
multivibrator.
`
tential applied to said supplementary electrode
12. In an electromagnetic deñection circuit for
by said applying means and the degree of de 10
exciting the winding of a deflection yoke the
combination of, an electron discharge tube hav
ing at least an anode, cathode, first control elec
varying means is so arranged that the amount of
trode and a second control electrode, means for
degeneration produced by said degeneration
means is` inversely proportional to the magnitude 15 applying a deñection signal between said ydis
` generation produced by said degeneration means.
8. Apparatus according to claim ’7 wherein said
of rvoltage applied to said supplementary elec
trode.
. 9. In a reaction scanning electromagnetic cath
charge tube first control electrode and said cath
ode, an output circuit for said discharge tube
connected between the anode and cathode thereof,
connections for driving the deflection yoke wind
>ode ray beam deflection system employing a de
rlection yoke having in shunt across its wind 20 ing from signal energy developed in said out
put circuit, a source of biasing potential having
ing a damping tube, the combination of a source
its negative terminal connected with said dis.
of deflection signal, an output tube having at
charge tube cathode and its positive terminal
least an anode,Y cathode control electrode and
connected with said discharge tube second ccn
supplementary electrode interposed between said
anode and said control electrode, connections 25 trol electrode, a degenerative network serially
included >in said connection to said second oon
for applying the output of said deñection signal
trol electrode, and means for varying the amount
source to said control electrode, an output cir
of degeneration produced by said degenerative
cuit connected between said anode and said cath
network whereby to control the amplitude of
ode, said output circuit including'means for cou
pling electrical variations developed therein to 30 deiiection produced by said discharge tube.
13. A cathode ray beam deflection system em
the deflection yoke, a source of positive biasing
ploying an electromagnetic deflection Vyoke in
potential having its negative terminal connected
combination, a deflection signal source having
with said output tube cathode, an impedance hav
output terminals, the vfrequency of the deiiection
ing a resistive component connected between said
supplementary electrode and the positive circuit 35 signal provided by said deflection source being a
function of the electrical capacity imposed across
of said biasing potential source whereby to in
said output terminals, an electron discharge tube
troduce degeneration in the deflection system,
having at least an anode, cathode and control
a capacitor connected in shunt with at least a
electrode, connections applying the output ter.
Yportion of said impedance to form a time con
stant combination, an inductance connected in 40 minals of said deflection signal source between
the control electrode and cathode for said dis
series with the shunt connections of the damping
charge tube, an output ,circuit connected between
tube across the yoke winding, resistance means
the said discharge anode and cathode, said out.
connected in shunt with said inductance, and
Dilt circuit including moans for coupling cleow
means for concomitantly varying both the time
constant of said time constant combination and 45 trical energy to Said. yoke, moans for varying the
frequency of deflection signal developed by .scid
the value of said resistance means whereby to
control the amplitude of deflection signal applied
to said deflection yoke.
` 10. In
a reaction
scanning
electromagnetic
deflection signal Source, controllable means for
imposing degeneration in Seid electron discharge
tube and coupling means connected between said
cathode ray beam deflection system employing a 50 frequency varying mea-ns and said controllable
means.
deiiection yoke having in shunt across its wind
14. Apparatus according to claim 13 wherein
ing a damping tube, the combination of a source
said electron discharge tube is of the screen
of deflection signal, an output tube having at
variety and wherein vsaid controllable degenera
least an anode, cathode control electrode and
supplementary electrode interposed between said 55 tion means is connected in the screen grid cir
cuit of said discharge tube and wherein said cou
anode and said control electrode, connections for
pling means comprises a connection from said
applying the output of said deflection signal
discharge tube screen grid to said frequency vari ~
source to said control electrode, -an output cir
ing means.
cuit connected between said anode and said cath
15. Apparatus according to claim 14 wherein
ode, said output circuit including means for cou 60
said source of deflection signals is a multi
pling electrical variations developed therein to
vibrator type sawtocth wave form generator hav
the deflection yoke, a source of positive biasing
ing the saw tooth discharge capacitor in shunt
potential having its negative terminal connected
with said output terminals.
with said output tube cathode, means for apply
16. An electromagnetic r.deflection circuit for
ing said positive bias source to said supplementary
exciting the winding of an electromagnetic de-Í
electrode, means to produce degeneration in said
flection yoke, a combination of an electron dis
output tube, an lnductance connected in series
charge tube amplifier having aV screen grid, an
with the shunt connection of the damping tube
input circuit and an output circuit, controllable
across the yoke winding, resistance means con«
nected in shunt with said inductance, and means 70 circuit means connected to said screen grid for
producing degeneration in said discharge tube
for varying the following three entities simul
ampliñer, means for coupling the deflection yoke
taneously ñrst the value of bias potential ap.
plied to said supplementary electrode by said
Winding with said amplifier output terminals to
applying means, second the degree of degenera
form an output _load for the ampliiier, means for
»tion produced by said degeneration means and 75 controlling the loss in said load, said loss con-4
2,579,627
13
trolling means and said degeneration controlling
being adapted to Work in synchronísm with one
another.
SIMEON I. TOURSHOU.
REFERENCES CITED
The following references are of record in the
ñle of this patent:
UNITED STATES PATENTS
Number
Name
Date
2,098,390
2,284,378
Iams _____________ __ Nov. 9, 1937
Dome ___________ __ May 26, 1942
14
Number
2,436,447
2,440,786
2,443,030
2,466,784
2,470,197
2,482,150
2,510,670
2,536,838
2,536,839
2,536,857
2,543,719
Name
Date
Packard __________ __ Feb. 24, 1948
Schade ___________ __ May 4, 1948
Foster ___________ __ June 8, 1948
Schade ___________ __ Apr. 12, 1949
Torsch ___________ __ May 17, 1949
Bocciarelli _______ __ Sept. 20, 1949
Trott _____________ __ June 6, 1950
Clark _____________ __ Jan. 2, 1951
Clark et a1 _________ __ Jan. 2, 1951
Schade ___________ __ Jan. 2, 1951
Clark ____________ __ Feb. 27, 1951