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Патент USA US3022469

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Feb. 20, 1962
3,022,459
D. ALPER .
PHASING APPARATUS
5 Sheets-Sheet 1
Filed NOV. 5, 1956
INVENToR.
DAV/D ALPER
BY
Feb. zo, 1962
D. ALPER
3,022,459
PHASING APPARATUS
3 Sheets-Sheet 3
Filed Nov. 5, 1956
FIG. 5
FIG. 4
0
A
0
A
45°- 90°
0°- 45°
B - VARIABLE
A - VARIABLE
FIG. 7
FIG 6
9o.
90°
I
B
0
I80«
Ia0°
A
F-IB
90"- I35°
A - VARIABLE
FIG. 9
FIG. 8
I80°
l80°
A
A
B
270°
225°- 270°
A - VARIABLE
FIG. I0
FIG. 11
^ A360°
270°
270"- 3Is°
A - VARIABLE
IN VEN TOR.
DAV/D ALPE/Q
BVM
'ice
3,022,459
Patented Feb. 20, 1962
2
3,622,459
as shown in FIG. 2, to provide a reference signal which is
applied to comparator 40 for comparison with a test sig
Corporation, a corporation of Delaware
Filed Nov. 5, 1956, Ser. No. 620,259
nal of unknown phase. The reference signal may be ad
justed within a phase angle of 45 degrees by changing
the amplitude of reference voltage B by moving contact
BHASING APPARATUS
David Alper, Fair Lawn, NJ., assigner to The Bendix
15 Claims. (Ci. 324-83)
The invention relates to electrical apparatus and more
particularly to phasing devices.
One object of the present invention is to provide ap
paratus which accurately indicates directly the phase angle
of a voltage of unknown phase.
Another object is to provide apparatus which provides
42 across resistor 44 of potentiometer 38. It is apparent
that when the amplitude of reference voltage B is zero
the reference signal will have a predetermined phase angle
and when the amplitudes of reference voltages A and B
are equal the reference signal will have a phase angle 45
degrees therefrom as shown by the dotted line in FIG. 2.
Reference signals within this range are produced by vary
ing the amplitude of reference voltage B on potentiometer
33 from zero to the same amplitude as reference voltage
voltages of any desired phase angle from 0° to 360°.
Another object is to provide apparatus with a high 15 A. The phase angle may be directly indicated on phase
input impedance using the null method to measure phase
indicator 46 operated by movable contact 42 of potenti
angles and which is insensitive to wave form.
ometer 38.
Another object is to provide apparatus which is highly
stable and accurate and provide for indications with high
resolution.
The invention contemplates a device for providing sig
nals of desired phase and for determining the phase angle
of a test signal. The phasing circuit apparatus is adapted
to provide a pair of reference voltages in quadrature with
one another and combines the voltages to provide a ref
erence signal. The amplitude of one reference voltage is
varied relative to the amplitude of the other reference
voltage to change the phase of the reference signal. The
Comparator 40 includes a dual triode having sections
48A, 48B functioning as cathode followers. Plates 50A,
20 56B of sections 48A, 48B are connected to B+ voltage
through decoupling resistors 52, 54 and to ground through
filter condensers 56, 58 in the usual manner.
Cathodes
60A, 60B of sections 48A, 48B are connected together
through a D.C. blocking condenser 62, primary winding
64 of a transformer 66, a potentiometer 75 and a T pad
65s’.
T pad 68 comprises variable resistors 70, 72, 74 ter
minating in potentiometer 75 and the T pad and potenti
ometer connect cathode 60B to ground.
The T pad is
provided to change the amplitude signals applied to trans
parator, and an indicator indicates the phase angle of the 30 former winding 64 from section 48B of the dualftriode
Without shifting the phase of the signal or changing the
signals when they are equalized.
.
bias on section 48B. Cathode 60A of section 48A is
The foregoing and other objects and advantages of the
reference signal and the test signal are applied to a com
invention will appear more fully hereinafter from a con
sideratíon of the detailed description which follows, taken
together with the accompanying drawings wherein one
embodiment of the invention is illustrated by way of eX~
ample. It is to be expressly understood, however, that
connected to ground through cathode variable bias re
sistor 76, the latter being used to initially balance the
gains of sections 48A and 48B of the dual triode. The
differential output of the cathode followers is applied
through secondary winding 78 of transformer 66 through
the drawings are for illustration purposes only and are
not to be construed as deñning the limits of the invention.
an ampliñer and filter 80 to a vacuum tube voltmeter 82.
lwith primary windings 14, 16 energized by alternating
mum or zero and the phase angle of the test signal may
A reference signal of known phase from phasing cir
40 cuits 9 is applied to grid 84A of section 48A and a tesi:
In the drawings:
signal, whose phase angle is to be determined, is applied
FIG. l is a schematic wiring diagram of a phasing de
to grid 84B of section 48B. Potentiometer 38 is ad
vice constructed according to the invention.
justed to vary the amplitude of reference voltage-B until
FIG. 2 is a diagram showing the manner of providing
the reference signal is in phase with the test signal. Also
voltages of any desired phase within a range of 45° from
T pad 68 is adjusted to vary the amplitude of the test
a pair of voltages in quadrature, and
signal at the output of cathode follower 48B until its
FIG. 3 is a schematic wiring diagram showing in more
amplitude is the same as the amplitude of the reference
detail the phase circuit of FIG. 1 to provide signals from
signal. T pad 68 provides a coarse adjustment of test
zero to 360 degrees.
signal amplitude and potentiometer 75 provides a line
FIGS. 4 to l1 are diagrams showingthe manner of pro
viding voltages of any desired phase from 0 to 360° from 50 adjustment of the test signal amplitude applied to trans
former 66. When the phase of the reference signal is the
a pair of voltages in quadrature with one another.
same as the phase of the test signal and when the ampli'
Referring now to the drawings for a more detailed de
'tude of the test signal applied to transformer 66 is the
scription of the novel phasing device of the present in
same as the amplitude of the reference signal applied to
vention, the device shown in FIG. l comprises phasing
circuits 9 having a pair of isolation transformers 10, 12 55 transformer 66, the vacuum tube voltmeter will read mini
be read directly on indicator 46.
current from any suitable source. Secondary winding
The arrangement described provides reference signals
18 of transformer 10 is connected through fixed resistor
in a range of` 45 degrees. However, it is desirable that
20 and variable condenser 22 in parallel and variable re
sistor 24 to ñxed resistor 26. The purpose of resistors 60 refernce signals from zero to 360 degrees be available and
a switching arrangement shown in IFIG. 3 is provided to
20 and 24 is to adjust the amplitude of the voltage across .
change the octant of the reference signals as shown in
resistor 26 to a suitable value. The purpose of condenser
FIGS. 4 to 11.
' ,
22 is to trim the phase of the voltage appearing across
In FIG. 3 a zero phase shift autotransformer 86 is con
resistor 26. With this arrangement, a first reference volt
age A of fixed phase and amplitude appears at resistor 26. 65 nected to an alternating current source of ñxed frequency
and is arranged for energizing the phasing circuits by al
Secondary winding 28 of transformer 12 is connected
ternating current voltages of various amplitudes. 'Iîhe
to a 90 degree phase shifting circuit, including condensers
auto-transformer is connected through a double-throw
30, 32, fixed resistor 36, variable resistor 37 and potenti
double-pole switch 88 to primary winding 116 of trans
ometer 38. A second reference voltage B having a lixed
phase 90 degrees out of phase with reference voltage A 70 former 112 and through switch 88 and ganged rotary
and of variable amplitude appears at potentiometer 38,.
' Reference voltages A and B are combined vectorially,
switches 90, 92 to primary winding 114 of transformer
110. Double-throw double-pole switch 88 simultaneously
3,022,459
4
reverses the phase of the voltage applied to both trans
formers 116, 112 and ganged rotary switches 90, 92 re
verse the phase of the voltage applied to transformer
110 relative to the phase of the voltage applied to trans
former 112. With this arrangement the voltages impressed
on transformers 110, 112 may be in phase or 180 degrees
out of phase with one another for the purpose described
hereinafter.
Y
Resistor 121i is connected in parallel with one condenser
4varied between 135 and 18()y degrees as shown in HG. 7,
Iand with switch t28 reversed the reference signal may be
varied between 315 and 360 >degrees as shown in FIG. ll.
It will be observed that when switches 93, 16d, ‘1514,
11.16 are in the second and ñfth positions potentiometer
144 is connected to the circuit including transformer 112
and ñxed resistor 126 is connected to the circuit including
transformer 110. Under these circumstances the ampli
tude of the reference voltage B from the circuit including
1.22, 222 or 322, through rotary switch 94 in position 2, 10 transformer 112 may be varied and the amplitude of refer
3 or 5 respectively as determined by the position of switch
ence voltage A from the circuit including transformer
94. In position 4 rotary switch 94 connects condenser
110 is fixed. When switches 9S, 10Q, 194, 106' are in the
422 in parallel with secondary winding 118. Secondary
third and fourth positions potentiometer 144 is connected
winding 118 of transformer 11i? is connected through re
to the circuit including transformer 1x16 and fixed resistor
126 is connected to the circuit including transformer 112.
Under these circumstances the amplitude of reference
voltage A from the circuit including transformer 11i) may
be varied and the amplitude of reference voltage B from
the circuit including transformer 112 is iixed. The refer
ence signal from the phasing circuit of FIG. 3 may be ap
plied to comparator 49 at grid 84A of section 48A of the
dual triode of the cathode follower circuit as shown in
FIG. 1.
The apparatus described provides reference signals of
any desired phase from zero to 360 degrees. The signals
are stable and the phase can be repeated accurately. The
sistor 120 and one of these condensers to one of the re
sistors 124, 224, 324 or 424 through rotary switch 96 as
determined by the position of switch 96. This circuit ar
rangement is connected to fixed resistor 126 or potenti
ometer 144 through rotary switches 9S, 160, 1%4, 166 as
determined by the positions of these rotary switches.
Secondary winding 123 of transformer 112 is connected
through condenser 1311 to one of variable resistors 137,
237, 337 0r 437 by rotary switch 102 as determined by
the position of the rotary switch. Secondary winding
123 of transformer 112 and condenser 131i are further
connected through condenser 132 and fixed resistor 136
to ñxed resistor 126 or potentiometer 144 by rotary
switches 98„ 11M), 104, 166 as determined by the positions
of these rotary switches. Rotary switches 93, Miti, 104,
and 106, as well as rotary switches 9i), 92, 94, 96 and
102 areganged together and are rotated by manually oper
ated octant selector 108. With `the switching arrange
ment described, various, combinations of resistance and
capacitance may be connected to the secondary windings
apparatus accurateyindicates directly the phase angle
of an unknown voltage and uses the null method of meas
urement in comparing phase angles. The apparatus has
a high input impedance and is insensitive to wave form.
Although but a single embodiment of the invention has
been illustrated and described in detail, it is to be ex
pressly understood that the invention is not limited there
to. Various changes may also be made in the design and
of transformers 11i) and 112 to generate reference volt
arrangement of the parts without departing from the
ages A and B across resistor 126 and potentiometer 144
spirit .andv scope of the invention as the same will now
be understood by those skilledv in the art.
What is claimed is:
withA known phase angles always 9()A degrees apart. Also
fixed resistor 126 is connected to one or the other of the
l. A device for providing signals of desired phase,
transformer circuits, and potentiometer 144 is connected
to the other transformer circuit so that only one of the 40 comprising a first phasing circuit adapted to be connected
to an alternating current source and> providing voltages
reference voltages can be varied in amplitude to provide
of a predetermined phase, a second phasing circuit
a referenceV signal of known phase which is indicated on
adapted to be connected to the alternating current source
phase indicator 146 drivably connected to movable con
and providing voltages in quadrature with the iirst volt
tact 142 of potentiometer 144.
ages, means for combining said voltages to provide a
The switching arrangement including rotary switches
signal, means for changing the amplitude of only one of
90, 92, 914, 96, 93, 160, 10,2, 104, 166 provides for shifting
the voltages relative to the other to provide signals having
the reference signal to a desired octant. Each rotary
phase angles variable Within a 45 degree range from a ref
switch has five ñxed contacts numbered 1 to S and a`
erence, and indicating means operable by the amplitude
movable Contact C. A_s indicated above, movable con
tacts C are gangedtogether and are drivably connected to 50 changing means for indicating directly the phase angle of
the signal relative to the reference.
anoctant selector provided with an indicator C' arranged
2. A device for providing signals of desired phase,
to~ move through tive positions numbered 1 to 5 corre
comprising a ñrst phasing circuit adapted to be connected
sponding tol iixed contactsl 1 to 5 of the switches. When
to an alternating current source and providing voltages
the octant selector is in the tirst position, as indicated in
FIG, 3, thel movable contacts C_ of the rotary switches 55 of a predetermined phase, »a second phasing circuit adapt
ed' to be connected to the alternating current -source and
are in corresponding position and the phase shifter is off.
providing voltages in quadrature with the first voltages,
When the octant selector is moved to the second position
switching means for reversing the phase angles of the first
thereference signal may be varied from zero to 45 degrees
and second voltages while maintaining the voltages in
as, shown in FIG. 4 with the reversible switch 88 in the
position shown. When switch 83 is reversed then the ref 60 quadrature with one another, means for combining said
voltagesto provide a signal, and means for changing the
erence signal may be varied between 180 and 225 de
amplitude of only one of the voltages to vary the phase
grees as shown in FIG. 8. When the octant selector is
of,v the signal relative to a reference, and indicating means
in position 3 and reversible switch 88 is in the position
operable by theV amplitude changing means for indicat
shownr in the drawing, then the reference signal may be
varied between 45 and 90 degrees as shown in FIG. 5. 65 ing directly the phase angle of the signal relative to the
reference.
When switch 88 is reversed then the reference signal may
3. A device for providing signals of desired phase, com
be varied between 225 and 270 degrees as shown in FIG.
prising a ñrst phasing circuit adapted to be connected to
9. Likewise when the octant selector is in the fourth
an alternating current source and providing voltages of a
position and reversible switch 88 is in the position shown
in FIG. 3 then the reference signal may be varied between 70 predetermined phase, a second phasing circuit adapted to
be connected to theA alternating current source and provid
90 and 135 degrees as shown in FIG. 6. When switch 88
ing voltages in quadrature with the first voltages, switch
isreversed then the reference signal may be varied be
ing means for reversing the phase angles of the first and
tween 270 and 315 degrees as shown in FIG. 10. With the
second voltages independently of one another While` main
octant selector in fifth position and reversible switch 88 in
the position shown` in FIG. 3 the reference signal may be 75 taining the voltages in quadrature with one another,
8,022,459
5
means for combining the voltages to provide a signal, and
means for changing the amplitude of only one of the
voltages relative to the other to vary the phase of the
signal relative to a reference, and indicating means oper
able by the amplitude changing means for indicating
6
receiving the -reference signal and the test signal and
having means for changing the amplitude of the test sig
nal without shifting its phase and for comparing the ref
erence signal and the test signal, and means operable by
the reference voltage amplitude varyin-g means to indi
directly the phase angle of the signal relative to the ref
cate directly the phase angle of the test signal upon equal
erence.
izing the signals.
4. A device for providing signals of desired phase,
9. A device for determining the phase angle of a test
comprising a first phasing circuit adapted to be connected
to an alternating current source and providing voltages of
signal, comprising phasing circuits adapted to provide a
pair of reference voltages in quadrature with one another
and to combine the voltages to provide a reference sig
nal, means for varying the amplitude of only one of the
to be connected to the alternating current source and pro
reference voltages relative to the other reference voltage
viding voltages in quadrature with the first voltages,
to vary the phase of the reference signal, a comparator
means for combining the voltages to provide a signal,
means for changing the amplitude of only one of the volt 15 receiving the reference signal' and the test signal and hav
ing a T pad for changing the amplitude of the test sig
ages to provide signals having phase angles variable
nal without shifting its phase and having means for com
within a 45 degree range from a reference, switching
paring the phase and amplitude of the reference signal and
means for connecting the amplitude changing means to
the test signal, and means operable by the reference volt
the first or the second circuit, and indicating means oper
able by the amplitude changing means for indicating di 20 age amplitude varying means to indicate directly the phase
angle of the te-st signal upon equalizing the signals.
rectly the phase angle of the signal relative to the ref
10. A device for determining the phase angle of a test
signal, comprising phasing circuits adapted to provide a
5. A device for providing signals of desired phase, com
pair of reference voltages in quadrature with one another
prising a first phasing circuit adapted to be connected to
an alternating current source and p-roviding voltages of 25 and to combine the voltages to provide a reference signal,
means for varying the amplitude of only one of the ref
a predetermined phase, a second phasing circuit adapted
erence voltages relative to the other reference voltage to
to be connected to the alternating current source and pro~
viding voltages in quadrature with the first voltages,
vary the phase of the reference signal, a comparator hav
ing a pair of cathode followers for receiving the reference
switching means for reversing the phases of the iirst and
second voltages while maintaining the voltages in quad 30 signal and test signal and having means for changing the
amplitude of the test signal without shifting its phase,
rature with one another, means for combining the volt
means connecting the cathodes of the cathode followers
ages to provide a signal, means for changing the ampli
for _comparing the phase and amplitude of the reference
tude of only one of the voltages to vary the phase of the
signal and the test signal, and means operable by the ref
signal relative to a reference, and indicating means oper
able by the amplitude changing means for indicating di 35 erence voltage amplitude varying means to indicate di
rectly the phase angle of the test signal upon equalizing
rectly the phase angle of the signal relative to the refer
the signals.
ence, and switching means for connecting the amplitude
11. A device for determining the phase angle of a test
.changing means to the first or the second circuit.
signal, comprising phasing circuits adapted to provide a
6. A device for providing signals of desired phase,
comprising a first phasing circuit adapted to be co-nnected 40 pair of reference voltages in quadrature with one another
and to combine the voltages to provide a reference sig
to an alternating current source and providing voltages of
nal, means for varying the amplitude of only one of the
a predetermined phase, av second phasing circuit adapted
reference voltages relative to the other reference voltage
to be connected to the alternating current source and pro
to vary the phase of the reference signal, a comparator
viding voltages in quadrature with the first voltages, means
for combining the voltages to provide a signal, means 45 having a pair of cathode followers for receiving the ref
erence signal and test signal and having a T pad in the
for changing the amplitude of only one of the voltages to
cathode follower circuit receiving the test signal for chang
vary the phase of the signal, an octant selector including
ing the amplitude of the test signal without shifting its
switching means for reversing the phases of the ñrst and
phase, means connecting the cathodes of the cathode fol
second voltages while maintaining the voltages in quad
rature With one another and for connecting the amplitude 50 lowers for comparing the phase and amplitude of the ref
erence signal and the test signal, and means operable by
changing means to the first or the second circuit, said
the reference voltage amplitude varying means to indicate
octant selector and said amplitude changing means co
directly the phase angle of the test signal upon equalizing
operating to provide signals with a phase angle variable
a predetermined phase, a second phasing circuit adapted
erence.
,
'
from zero to 360 degrees from a reference, and indicat
the signals.
ing means operable by the amplitude changing means for 55
indicating directly the phase angle of the signal relative
12. A device for determining the phase angle of a test
signal, comprising a first phasing circuit adapted to be
to the reference.
connected to an alternating current source and providing
voltages of a predetermined phase, a second phasing cir
cuit adapted to be connected to the alternating current
signal, comprising phasing circuits adapted to provide a
pair of reference voltages in quadrature with one another 60 source and providing voltages in quadrature with the lirst
voltages, switching means for reversing the phase angles
and to combine the voltages to provide a reference sig
of the first and second voltages While maintaining the
nal, means for varying the amplitude of only one of the
voltages in quadrature with one another, means for com
reference voltages relative to the other reference voltage
bining said voltages to provide a reference signal, means
to vary the phase of the reference signal, a comparator
receiving and com-paring the reference signal and the test 65 for changing the amplitude of only one of the voltages
to vary the phase angle of the reference signal, a compara
signal, and means operable by the amplitude varying
tor receiving and comparing the reference signal and the
means for indicating directly the phase angle of the test
test signal, and means operable by the amplitude varying
signal when the signals are in phase with one another.
means for indicating directly the phase angle of the test
8. A device fordetermi-ning the phase angle of a test
signal, comprising phasing circuits adapted to provide a 70 signal when the signals are in phase with one another.
13. A device for determining the phase angle of a test
pair of reference voltages in quadrature with one another
signal, comprising a first phasing circuit adapted to be
and to combine the voltages to provide a reference _sig
connected to an alternating current source and providing
nal, means for varying the amplitude of only one of the
voltages of predetermined phase, a second phasing circuit
reference voltages relative to the other reference voltage
to vary the phase of the reference signal, a comparator 75 adapted to be connected to the alternating current source
7. A device for determining the phase angle of a test
annalisa
7
and providing voltages in quadrature with the first vol*
ages, switching means for reversing the phase angles of
>the ñrst and second voltages independently of one an
other while maintaining the voltages in quadrature with
one ano-ther, means for combining the voltages to provide
a reference signal, means for changing the amplitude of
only one of the voltages relative to the other to vary the
phase angle of the reference signal, a comparator receiv
ing the reference signal and the test signal and having a
pair of cathode followers for receiving the reference sig
nal and test signal and having means for changing the
¿i
voltages to vary the phase of the signal, an octant selector
including switching means for reversing the phases of the
rst and second voltages while maintaining the voltages
in quadrature with one another, and for connecting the
» amplitude changing means to the lirst or the second cir«
cuit, said octant selector and said amplitude changing
means cooperating to provide signals with phase angles
variable from zero to 360 degrees, a comparator having
a pair of cathode followers for receiving the reference sig
nal and the test signal, a T pad in the cathode follower
circuit receiving the test signal for changing the ampli
amplitude of the test signal without shifting its phase,
means for comparing the phase and amplitude of the ref
erence signal and the test signal, and means operable by
tude of the test signal without shifting its phase, means
connecting the cathodes of the cathode followers for
the voltage amplitude changing means to indicate directly
the phase angle of the test signal upon equalizing the
nal and the test signal, and means operable by the voltage
amplitude changing means to indicate directly the phœe
angle of the test signal upon equalizing the signals.
signals.
14. A device for determining the phase angle of a test
signal, comprising a first phasing circuit adapted to be
connected to an alternating current source and providing 20
voltages of a predetermined phase, a second phasing cir
cuit adapted to be connected to the alternating current
source and providing voltages in quadrature with the ñrst
voltages, means for combining the voltages to provide
a signal, means for changing the amplitude of only one 25
of -the voltages to vary the phase of the signal, an octant
selector including switching means for reversing the
phases of the tiret and second voltages While maintaining
the voltages in quadrature with one another and for con
necting the amplitude changing means to the ñrst or the 30
second circuit, saidy octant selector and said amplitude
changing means cooperating to provide signals with phase
angles variable from zero to 360 degrees, a comparator
receiving and comparing the reference signal and the test
signal, and means operable by the voltage amplitude
changing means for indicating directly the phase angle
of the test signal when the signals are in phase with one
another.
15. A device for determining the phase angle of a test
comparing the phase and amplitude of the reference sig
References Cited in the file of this patent
UNITED STATES PATENTS
1,495,466
2,408,193
2,414,475
Marchand ___________ __ Jan. 21, 1947
2,471,105
2,481,492
2,532,368
2,606,966
Gustafsson et al. ______ __
Bjarnason ____________ __
Malmquist ___________ __
Pawley ______________ __
May 24,
Sept. 13,
Dec. 5,
Aug. 12,
1949
1949
1950
1952
2,672,588
Vanous _____________ __ Mar. 16, 1954
2,684,443
2,751,555
2,762,012
Tidball __"____________ __ July 20, 1954
Kirkpatrick __________ __ June 19, 1956
Kaltenbacher _________ __ Sept. 4, 1956
' 2,794,948
2,857,568>
Thompson et al. ______ __ June 4, 1957
Hering ______________ __ Oct. 21, 1958
2,863,117
Graustein` ____________ __ Dec. 2, 1958
2,911,592
Colliery et al‘___________ __ Nov. 3, 1959
617,568
Germany ____________ __ Aug. 23, 1935
FOREIGN PATENTS
signal, comprising a ñrst phasing circuit adapted to be
OTHER REFERENCES
connected to an alternating current source and providing
voltages of a predetermined phase, a second phasing circuit
adapted to be connected to the alternating current source
and providing voltages in quadrature with the iirst volt
ages, means for combining the voltages to provide a signal,
means» for changingA the amplitude of> only one of the
Wente ______________ __ May 27, 1924
Beste _______________ __ Sept. 24, 1946
“Direct Reading Phasemeter,” article in The Review
of Scientific Instruments, April 1950; pp. 271-273.
“A Simple Variable Frequency Phase Measuring De,
vice,” article in Electronic Engineering, September 1952;
pp. 402, 403.
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