Commercial Cathoderay Oscillographs

We now are ready to consider the structure of the cathode-ray oscillographs offered for commercial use. Let it be known that it is our intention to discuss those devices which are being offered for use by the radio servicing industry for radio receiver design and servicing, public address design and servicing and to the amateur radio fraternity, for the adjustment of ham transmitters. There are in use a large number of cathode-ray units intended for the industrial field and college...

Stated in the preceding paragraph the tube itself is but one part of the

The trace or pattern or image, which appears upon the viewing screen, provides a visual means of studying transient or recurrent electric or magnetic phenomena. The nature of the phenomena, which can be studied, is extremely diversified, due primarily to the fact that the electron beam or stream is practically free of inertia consequently it can respond to cyclic variations from a fraction of a cycle per second to several hundred million cycles. Frankly, at the time of this...

What Is in the Cathode Ray Tube

You wonder about the structure of a cathode-ray tube. Once more we repeat that our discussion, consequently our descriptions, relate to those tubes that are used in commercial oscillographs, which employ the cathode-ray tube and which are being offered to the radio servicing industry and related industries for the work previously mentioned. We include these qualifications in order to obviate the necessity of describing other types of cathode-ray tubes, of the very high voltage variety used in...

Input and the modulated wave envelope The standards of comparison

Fig. 421 shows the modulated wave for correct tuning of the plate tank. Fig. 422 shows the corresponding trapezoid. Fig. 423 shows the modulated wave for incorrect tuning of the plate tank and Fig. 424 shows Fig. 428 (left) shows the modulated wave envelope when the modulator is matched to a 2000-ohm load. The corresponding trapezoidal pattern is shown in Pig. 429 (middle) and the audio voltage across the modulator load is shown in Fig. 430 (right). Compare these images with Figs. 393 and 394....

VVW

When the volume control was further advanced the ends of the voltage characteristic became slightly flattened, see Fig. 191, and a change from a sine wave is evident in the output wave, see Fig. 192. trol developed the input-output voltage characteristic shown in figure 191 and the resultant waveform is shown in figure 192. Flattening of both ends of the voltage characteristic is evident and the distortion introduced is shown in the departure of the output wave from...

Tubes With No Plates or One Pair

There are tubes, as has been stated, which contain but one pair of deflecting plates and outside magnetic deflection coils must be employed. Then again, there are cathode-ray tubes without any deflecting plates within the glass envelope and magnetic deflection must be used. These are general descriptive references. The types of tubes, which are used in connection with radio receiver design and servicing, invariably are of the type equipped with two pairs of internal deflecting plates, and are...

Varying Voltages Applied to Deflector Plates

Up to the present time, we have devoted our attention to deflection of the electron beam by means of d-c. voltages applied to the vertical and horizontal plates. Let us now consider the application of varying voltages, such as a-c. potentials. What is the effect of such voltages when applied to the deflecting plates In the first place, the process of deflection is exactly as before, that is, with d-c. voltages. The displacement of the beam from its normal center position is again a function of...

Ac Voltages On Both Sets Of Plates

Before embarking upon the discussion of the commercial cathode-ray oscillographs and the practical application of such units, there is one very important subject which must receive attention. This is the result of applying a-c. voltages to both sets of deflector plates. In this connection one very important point comes to the fore. This is phase relation. The phase relation between the a-c. voltage applied to the vertical deflection plates and the a-c. voltage applied to the horizontal...

Focusing in Other Types of Tubes

You may have noted that the focusing of the beam in the RCA type of tube is a result of the fields developed by the voltages applied to the anodes. In other words, the concentration of the electrons into a beam is accomplished by these fields. The Western Electric tube employs a somewhat different manner of concentration. We stated in connection with the electrode arrangement shown in figure 2, that the tube contained a cathode, a shield and an anode. In contrast to the fixed potential cathode...

Points and finally to which is zero At the same time the rotor arm is advancing in its arc of travel Having

Passed the zero point, it is making horizontal deflector plate HDP-2 positive with respect to HDP-1, so that the spot is positioned to the right of the Y axis, or vertical reference line. Furthermore, the wave is still above the X axis or horizontal reference line and vertical deflector plate VDP-1 is still positive with respect to VDP-2, so that the spot positions are still above the horizontal axis. During the time that the wave is passing through its second quarter cycle, the rotor arm is...

John F Rider

Servicing Receivers by Means of Resistance Measurement Perpetual Trouble Shooter's Manual Volume III Volume IV Volume V Volume VI Volume VII Volume VIII Volume IX Volume X Volume XI Volume XII Volume XIII Volumes I to V Abridged Automatic Record Changers and Recorders Aligning Philco Receivers, Volumes I and II Resonance and Alignment Automatic Volume Control Alternating Currents in Radio Receivers D-C. Voltage Distribution in Radio Receivers

We now reduce the frequency of the sweep circuit and after a number of complex images appear we develop three cycles

The sweep amplitude adjustment is the same as it was for figure 67-C. The three cycles are shown in figure 68-A. It now is possible to judge the character of the wave. We reduce the amplitude of the sweep voltage by varying the amplifier control. The vertical deflection plate amplifier has not been changed, as is shown by the uniform vertical amplitude. The new image appears as in figure 68-B. If you compare figures 68-A and 68-B, you will note that the rounded tops of the sine waves appear...

Info

Daring one half of each revolution of the variable condenser in the frequency modulator of Fig. 256, the sweep circuit is shorted and only cycle N spreads the resonance curve, giving a single instead of a double pattern. Fig. 275. Daring one half of each revolution of the variable condenser in the frequency modulator of Fig. 256, the sweep circuit is shorted and only cycle N spreads the resonance curve, giving a single instead of a double pattern. circuit, which is shorted during the...

How the Cathode Ray Tube Works

As is true in any number of instances, best utilization of a piece of equipment is obtained when the operator is thoroughly familiar with the operation of the device. That is why we place such importance in knowing how the electron beam in the cathode-ray tube is controlled at the various electrodes. If the focusing of the tube and the effect of the various electrodes is fully comprehended, some of the peculiar effects encountered with these tubes will be recognized and corrective measures...

Actual interpretation of the patterns it might be well to furnish a few

Pertinent facts pertaining to the application of the cathode-ray tube oscillograph to this type of work. As a general rule, frequency comparison or frequency calibration with the cathode-ray tube is usually applied to frequencies from 0 to about 100,000 cycles. Not that the cathode-ray tube is encumbered by this figure as its upper limit, but rather because this figure is the upper limit of amplifiers, which can develop sufficient voltage to provide suitable deflection upon the screen. As a...

Ja Aa

These oscillograms are examples of asymmetrical resonance curves, like those which were developed in Figs. 263 and 264. The differences between these curves are explained in the text. tions of figures 262, 263 and 264, is to be expected. In actual practice, however, you may experience quite a different condition. The graphic illustrations of figures 262 to 264 cannot take into consideration such an item as regeneration, which is present to a lesser or greater...

Has the intensity control although not in the same manner as the other

The number of electrons fed into the beam or allowed to pass through the shield (electron gate) aperture is controlled by the emission of the cathode, because the shield, being joined to one side of the cathode, is maintained at a fixed potential with respect to the cathode. At the same time, the anode, being at a fixed potential, supplies the attracting influence upon the electrons to cause them to move through the shield aperture and accelerates their motion towards the screen. With...

Aw

Further changes were made in the value of C of Fig. 201. When it was increased to .01 mf. the wave shown in Fig. 204 was obtained and when it was made .05 mf., the waveform of Fig. 205 was obtained. Note the similarity of this wave to the original, which is shown nevertheless very conclusively. A very excellent method of checking phase distortion in amplifiers, known to be free from frequency dis crimination or frequency distortion, is to pass a fairly linear...

Optical Analogy of Focusing

Suppose that we consider a simple optical system, such as that shown in figure 5. The variables which present themselves in this analogy, Fig. 5. A sketch of an optical system that is analogous to the elements of an RCA cathode-ray tube. L is a light source, whose output can be controlled by the variable opening of the shutter S. O and P are lenses, which concentrate the beam to a spot on the screen Sc. are very much like the variables which are found in the RCA type of cathode-ray tube. You...

Published By

404 Fourth Avenue New York City All rights reserved, including that of translation into the Scandinavian and other foreign languages FIRST PRINTING, AUGUST, 1935 SECOND PRINTING, OCTOBER, 1935 THIRD PRINTING, JUNE, 1936 FOURTH PRINTING, APRIL, 1937 FIFTH PRINTING, DECEMBER, 1937 SIXTH PRINTING, APRIL, 1939 SEVENTH PRINTING, JULY, 1940 EIGHTH PRINTING, MAY, 1941 NINTH PRINTING, NOVEMBER, 1941 TENTH PRINTING, MARCH, 1942 ELEVENTH PRINTING, MARCH, 1942 TWELFTH PRINTING, MAY 1942 THIRTEENTH...

R r r r

Oscillograms in Pigs. 359, 360 and 361 were made with the vibrator of Fig. 353 functioning as a half-wave rectifier by disconnecting contact A. Oscillogram made when contact A was restored to normal operation is shown in Fig. 362. When both contacts were opened to maximum separation, oscillograms in Figs. 363 and 364 were obtained across PI and SI and their respective center taps. 356 and 357 respectively. The voltage waveform between points V and VI is shown in figure 358....

Weep Ckcxe O

The sweep frequency is here twice what it was in Fig. 261. Cycle N of the sweep spreads the frequency modulated output from 450 kc. to 470 kc. over the screen and cycle O spreads the descending part of the output. Points A to E and A' to E' coincide on the screen. See Figs. 272 to 274. screen during 180 degrees of the condenser rotor movement, returns to its initial starting position and then again sweeps the spot across the screen during the remaining 180 degrees of rotation of the...

The Western Electric

Figure 2 illustrates the physical structure of the W.E. type 224 cathode-ray tube. The working elements are enclosed within a pear-shaped glass bulb about twelve inches long. All air is removed from the bulb and a certain amount of argon gas is placed within it. The purpose of this gas is to aid in the concentration of the beam. Figure 2 illustrates the physical structure of the W.E. type 224 cathode-ray tube. The working elements are enclosed within a pear-shaped glass bulb about twelve inches...

The RCA cathoderay oscillograph which employs the tube is rated at about volts per inch In other words if a dc voltage

72.5 volts is applied across either set of plates, the spot will move a distance of about 1.0 inch from its normal center position. However, this calibration holds true only if the tube is being operated at the specified potentials, so that for any type of quantitative work, pre-cali-bration by means of known values of d-c. voltage is suggested, as a matter of fact, actually required. Based upon this rating, it stands to reason that the cathode-ray tube is not the most satisfactory for low...

Sweep Circuits

The greatest amount of the discussion presented thus far concerned the action of the deflecting fields upon the electron beam and the positioning of the spot. We progressed through the application of d-c. voltages to the vertical and horizontal deflection plates and have made very brief mention of the application of a varying or a-c. voltage to the deflection plates. Now, the primary function of the cathode-ray tube as used in oscillographs employed in connection with radio receiver and...

General rule the deflection representing amplitude is usually applied to

The vertical deflection plates and the deflection representative of the time is applied to the horizontal deflection plates. You can very easily comprehend the absence of the time base, by examining figure 24. While it is true that the deflecting force applied to the vertical plates is that of an a-c. voltage wave, the image upon the screen is a single straight line of just one dimension. The time base is absent. Such would be the image for any type of waveform applied to the vertical...

Indicated in the trapezoid by the light and dark portions

Fig. 413 (left) indicates the modulated wave during excessive regeneration and Fig. 414 (middle) shows the equivalent trapezoidal pattern. Fig. 414-A (right) is another trapezodial pattern indicating improper neutralization Fig. 415 (left) indicates the modulated wave. Fig. 416 (middle) shows the equivalent trapezoidal pattern and 417 (right) shows the audio wave across the modulator output. Note that the oscillation starts suddenly, persists for awhile and then dies out during each cycle. Note...

Examine figure This is the characteristic of a resonated transformer used in the if circuit The frequency modulated

Into this device and the sweep circuit is synchronized in such manner that the start of the sweep occurs when the frequency modulating condenser is at full capacity and the frequency is the lowest. The numbers upon curve A in figure 263 are reference figures to indicate the response of the circuit at the various frequencies. During one half of the sweep cycle, curve B is developed and during the remaining half of the sweep cycle, curve C is developed, curves B and C appearing simultaneously...

Shown in figures and If the nature of the ac voltage is such

That the amplitude of its alternations is not equal, then the displacement of the spot both sides of the normal center position along the vertical or Y axis will not be the same, but will be in accordance with the peak voltage of the alternations. There is one other significant fact which must be mentioned in connection with varying voltage applied to the deflection plates. In actual practice, the image which will appear upon the viewing screen will be a line image or pattern, because, as a...

Other Applications Of The Cathoderay Oscillograph

In line with the statement that the cathode-ray oscillograph can be used for the observation of various electrical phenomena, are observations of value in connection with the academic study of radio principles. There are a number of subjects, which require extensive descriptive discussion, particularly when variables are involved. A great deal of time can be saved by the use of the cathode-ray oscillograph to illustrate the effect of these variables upon the final pattern. Take for example the...

We used very low values for R as low as or ohms However

With higher values of input voltage, so that saturation can be established by varying the input signal voltage, the value of this resistor may conveniently be a 100 ohms or more. The ideal B-H curve is a single straight line. Saturation of the core, with its detrimental effects, is indicated by the flattening of the ends of the loop, as indicated in figures 142, 143, 144 and 145. The most pronounced case of saturation, with respect to the instances being shown, is that indicated in figure 142....

Introduction

The cathode-ray oscillograph is not a new device. It is years old. In fact the writer employed the instrument almost a decade ago and there were very many who employed it many years before then. However, its exploitation during the past six months removed it from the laboratory class and made it an instrument of general practical utility to an extent far greater than that which was accomplished during the past ten years. . . Radio service technicians design engineers college laboratory...

Is sufficient to separate the peaks

Ratios as high as 10 to 1 can be easily observed with patterns such as that shown in figure 50. In each case tangents drawn to two sides and counting the number of loops or peaks which touch these tangents will identify the frequency ratio. Such identification requires that one frequency be known and further that the plates to which this voltage has been applied, be known. The relation between the frequency of the voltage and the plates to which the voltage has been applied is important,...

Direction then in the other direction

Starting from minimum capacity, we find that two positions of the condenser rotor result in the same frequency. We now have an option of using these two positions or short circuiting the condenser during 180 degrees of its travel, so that the frequency is swept through the band only once in each complete arc of travel of the condenser rotor. Both of these methods are used, as you will see. The RCA frequency modulator sweeps through the band twice, whereas the Clough-Bren-gle unit employs the...

What Is the Cathode Ray Tube

The cathode-ray tube is essentially a special type of vacuum tube, wherein electrons emitted from a cathode are concentrated into a beam, which beam is placed under the influence of electric or magnetic, or a combination of both, fields and then caused to impinge upon a specially prepared screen, located within the tube. This screen becomes fluorescent at the point of impact of the electron beam and thus makes visible the trace of the beam in the form of a pattern or image. The persistency of...

Transmitter Adjustment

The cathode-ray oscillograph is of excellent utility during the adjustment of a transmitter. While it is true that our experimental work did not cover all types of transmitters, we feel that the oscillograms presented in the following pages should serve as guides to those men, particularly the amateurs, who operate low powered ham transmitters and who have been interested in the application of the cathode-ray oscillograph as a means of adjusting correctly the various circuits which comprise the...

Positioning of the Spot

From what has been said thus far, you can no doubt appreciate that by the application of a fixed voltage from a battery, it is possible to position the spot wherever desired. We have mentioned time and again that under normal conditions, with zero potential difference between the plates of each pair of deflector plates, the normal position of the spot is at the center of the screen. Now it is possible that for some reason, it may be desirable to place the normal position of the spot somewhat...

Hb

Applying positive voltages to the plates VDP-1 and HDP-2 by means of the batteries and potentiometers, the beam's spot can be placed ANYWHERE in quadrant A, see Fig. 16-A. The solid spots, 1 to 7, indicate the resultant positions of the beam's spot, when acted upon by the white dots IV to 7V and 1H to 7H respectively. axis, that is the vertical axis, is the same as for the vertical deflection, without any horizontal deflection, and that its displacement from its basic position along...

Mm I Aw

The original wave fed into the phase distorting circuit is shown in Fig. 202. When the condenser C (Fig. 201) was made .005 mf the waveform of Fig. 203 resulted. that shown in figure 204. With C changed to ,05-mfd. the wave shape became that illustrated in figure 205. The gradual approach to the original waveform is evident. It was attained when C was increased to ,5-mfd. No doubt a certain amount of frequency discrimination was also present in the system, but the...

O j

Variation in voltage output may exist over the band used, but we shall assume for our discussion that the voltage output is of constant amplitude. The selection of the 450 kc. to 470 kc. band is purely illustrative. We assume that similar conditions prevail over any band width both sides of any periodic or mean frequency. It should be realized that a departure from such linearity of output will distort the final resonance curve. We stated that the change in frequency, with motor driven...

Does not very greatly interfere with the operation of the tube provided of course that the degree of misalignment of

Fig. 8 A shows the relative position of the deflecting plates of a Western Electric type of cathode-ray tube. Note that each pair of plates is parallel. Fig. SB shows how the plates of an RCA tube are at an angle to each other. It should be noted that the longer sides of each pair are perpendicular in so great as to interfere with the image upon the screen. If sufficient screen area is available for whatever utility is expected from the tube, a slight shift in spot centering does not do a great...

Magnetic Deflection

All of the comments made thus far concerning deflection of the electron beam referred to the application of voltages to the deflecting plates. The beam may also be deflected by means of a magnetic field, by placing the electron beam under the influence of a magnetic field. The magnetic field is created by means of a pair of coils located outside the tube near the neck. The extent of the deflection is determined by the strength of the magnetic field, which in turn is determined by the current...

L Linearference

Speaking about the filtering action of the units in a power supply device, figure 247 illustrates a two-section filter, which is tested along the following lines in order to establish the value of the various units The vertical deflection plate leads, shown in figure 246, would be connected across the common connection and point 1, for the overall hum. Across points 1 and 2, would develop the a-c. voltage across the choke L-l. Across the common connection and point 2, would develop the a-c. hum...

Ww

The input-output signal voltage characteristic of the a-f. amplifier of a receiver with a medium setting of the volume control, which was the diode's load, is shown in Fig. 189. The sine wave output is shown in Fig. 190. As is happens, this triode received its bias from the diode load resistance. For a medium setting of the volume control, which was in the grid circuit of the triode portion, the resultant input-output voltage characteristic is shown in figure 189...

Practical Application Of The Cathoderay Oscillograph

Practical applications of the cathode-ray oscillograph, there are plenty. To present a list of its practical uses and to enumerate again these units in connection with the actual work, would be just so much duplication. Accordingly, we shall omit the usual list and consider each application in turn. When talking about certain operating characteristics of cathode-ray oscillographs, we must take for granted that you who read these pages possess the type of equipment which is covered by this text....

To the center of the trace the receiver tuning can be changed and the

Cathode Ray Tube Diagram

Amount by which it must be changed to bring the peak to the center indicates how far off the receiver calibration is. Referring back to Fig. 447, the peak was brought to the center by changing the receiver tuning from 600 kc. to 595 kc. This means that the receiver calibration at 600 kc. is off by 5 kc. It should be clearly understood that the optimum adjustment is attained when the r-f. and detector stages are tuned to the incoming signal and the oscillator frequency is higher than the signal...

Around a glass cylinder

In order to facilitate observation or to simplify the pattern, it is frequently desirable to separate the front and rear patterns. In other words, patterns, such as we have shown, can be said to have front and rear portions, which are on the same horizontal plane. That is why, under certain phase conditions, certain peaks or loops are covered by Fig. 120. This circuit is used for separating the front and rear portions of a pattern, making the interpretation of high ratio figures much simpler....

Alignment Of Tuned Circuits

The alignment of a tuned circuit, so as to establish the correct resonant state by visual observation, is commonly understood to be the most valuable application of the cathode-ray oscillograph. Having read through this volume up to this point, you no doubt appreciate our statement when we say that observation of resonant circuits is but one more application of the cathode-ray instrument we are discussing. It is true, however, that, from the viewpoint of the servicing industry, it is an...

L

Schematic diagram of a beat frequency oscillator which is frequency modulated by the motor driven variable condenser in the lower left corner of the diagram. This type of oscillator, when frequency modulated, provides a band width that is constant for any output frequency. In contrast to the single oscillator type of frequency modulated source of test signal, there is in use the dual oscillator system, operated with a motor driven frequency modulator condenser, whereby a constant band...

The Deflection of the Beam

There are two important functions performed in the cathode-ray tube oscillograph. The first is the focusing of the electron stream into a narrow concentrated beam of electrons. The second is the placement of this beam under the influence of an electric or magnetic, or combination of both, types of field, in order to secure the proper deflection of the beam. Deflection of the beam results in a pattern or image visible upon the fluorescent viewing screen, which pattern furnishes the information...

Jvw

Fig. 229-A, left, Fig. 229-B, middle, Fig. 229-C, right. A. The wave envelope of the modulated output of a commercial test oscillator. B. The a-f. output of the same oscillator. C. The a-f. signal resulting from demodulation of the modulated wave shown in A. Concerning modulated wave patterns, the design of the majority of commercial service test oscillators, with possibly one or two exceptions, is such that the modulated waveform varies with the frequency setting of the test oscillator....

Focusing the RCA Type Cathode Ray Tube

Let us now associate figure 5 with the electrodes used in the RCA type cathode-ray tube and see how closely the optical analogy of focusing is like the electrical means employed in the tube. Examine figure 6. H is the heater. C is the cathode, which is the electron emitter and equivalent to the light source. G is the control grid and is the equivalent of the light gate, or stop S. Just why this is so will be stated later. Anode Al is the equivalent of lens O and anode A2 is the equivalent of...

Transformer windings which is related to the starting winding This

Non Synchronous Vibrator

Winding shunts one half of the primary winding in all full wave, synchronous and non-synchronous vibrator systems. The oscillograms we shall show will serve to illustrate how the cathode-ray oscillograph can be used to establish the effect of various adjustments, showing that various changes in adjustment and circuit constants influence the voltage waveform and proper interpretation should lead to most efficient servicing. The schematic wiring diagram of the full-wave non-synchronous vibrator...

Table Of Contents

What the Cathode-ray Tube is and What it will do 1. Types of Cathode-ray Tubes 2. What is in the Cathode-ray Tube 6. The Western Electric 224 Tube 7. The RCA 906 Tube 8. How the Cathode-ray Tube Works 10. Optical Analogy of Focusing 11. Focusing the RCA type Tube 14. Focusing in Other types of Tubes 17. Magnetic Focusing 19. Beam Deflection 20. Tubes with No Plates or One Pair 20. Beam Deflection in Different types of Tubes 21. Spot Positioning 30....

O

The schematic diagram of the RCA Model TMV-122-B cathode-ray oscillograph. NOTE C-21 not included on all instruments. cerned, the instrument consists of a type 885 grid controlled gas triode, which is in effect a thyratron, as the saw-tooth wave-time axis oscillator, two individual resistance-capacity coupled amplifiers, a two-tube rectifying system, one tube functioning as a full-wave rectifier supplying the plate and grid voltages for the two amplifiers and the other tube functioning as a...

Index

See Resonance Curves at wrong frequency, 269 Automatic Frequency Control, 332 circuit connections, 260, 266 incorrect band width, 269, 271 insufficient band pass, 271 rectification for visual, 257 requirements for correct, 261 600 kc., 320 Amplifier See Resonance Curves calibration of oscillograph gain controls, 176, 177 checking audio overload of, 188, 189, 190, 191, 192, 193 checking Class B, 201, 202, 203, 204 checking frequency response of, 280-286, 315 checking Class C See Transmitter...

Clough Brengle Model 210 Rf Signal Generetor

The schematic diagram of the Clough-Brengle Model OM frequency modulated r-f. oscillator. The 76 tube in the middle of the diagram is the constant frequency oscillator that is frequency modulated by the motor driven condenser at the left. be used with any r-f. oscillator of suitable frequency range required to cover all operating bands. The Clough-Brengle OM frequency modulated r-f. oscillator is shown in figure 278. The type 76 tube nearest the 6A7 mixer is the variable band...

Persistency of Vision

At this time it is imperative to bring one pertinent fact to your attention. You have read repeated references to SPOT positions. While these may have appeared repetitive and perhaps superfluous, the frequent references were premeditated. We want to impress upon you that the electron beam causes a fluorescent spot to appear upon the screen at the point where the beam strikes the screen. Irrespective of the nature of the voltage impressed upon the deflecting plates, it is only a single spot...

Appendix

Reference is made on pages 216 and 217 to testing mixer systems for distortion. This can be done by using the tuned amplifier mentioned in this volume. The signal from the test oscillator is fed through the amplifier to the cathode-ray tube and the character of the modulated wave is observed. This can be done at frequencies as high as several megacycles, providing that the modulated carrier signal is fed directly to the vertical deflection plates, without passing through the vertical deflection...

Dotted line and the position of the spot upon the screen is When

The difference of potential previously described exists between the plates, the beam is pulled out of line as it passes between the plates and the spot upon the screen is moved to the point indicated by the number 1, the beam being shown as a dotted line. The extent that the spot is moved up away from its normal position, or the extent of the pull upon the beam towards the upper plate DP-1, is determined by the preponderance of the positive charge upon this plate, with respect to plate DP-2. If...