DE2003876B2 - LINE DEFLECTION FOR 110 DEGREE COLOR TUBES - Google Patents

Description

At the transition from the previous 90 "deflection for 110 ° deflection in color television receivers problems arise, which new circuits have to overcome and components required.

For example, it is known that the temperature at 110 ° - Color picture tubes for the horizontal and vertical deflection, the deflection power to be applied is considerably greater than with the 90 ° color picture tubes used up to now.

A simple conversion of the 90 ° technique, as it is carried out with the transition from 70 ° to 90 "color picture tubes is not possible because the dynamic convergence at 70 ° and 90 "picture tubes for both deflection directions contain essentially linear terms, while a correction for 110 ° picture tubes with product links is required.

For the 110 ° technology, a new horizontal deflection circuit is required above all, with one frame-rate parabola modulation of the horizontal deflection current for horizontal raster correction and an additional stream for dynamic corner convergence necessary is. This additional current, which is proportional to the product of the vertical and horizontal deflection current must be, is generated in a special circuit and the deflection coils must be symmetrical flow through.

Although the required deflection power with a reduction in the tube neck diameter is a 110 "color picture tube would have been lower for reasons the picture quality is a comparatively thick-sharked one Picture tube chosen for a deflection power that is slightly more than twice as high as the 9Q ° color picture tube is needed.

ι Because it was assumed that to generate this high deflection power from the line end tube Maximum power to be delivered above the limit power data of one of the currently available Tube types is located, a circuit has already been made

ίο with two line end tubes and two transformers suggested. It is true that the requirement is for an additional current to be symmetrical in both halves of the deflection coils feed, can be fulfilled with this circuit, but with this arrangement the circuit complexity is approximately

π twice as large as the one common for 90 "technology Circuit with only one output tube and one transformer.

Since also the fields for the raster correction and for the necessary dynamic convergence because of

2i) the larger deflection angle for 110 ° color picture tubes Must be about twice as large as with 90 ° deflection, are in the proposed two-transformer concept active correction circuits used because passive transductor circuits, like

they are used in the 90 ° technique, according to the generally prevailing view for the required Screen correction is insufficient or can only be achieved with a great deal of effort.

It is desirable to avoid the high technical complexity of a line deflection circuit described above for 110 ° color picture tubes and to look for a solution that is similar to the 90 ° technique only a tailpipe and a transformer required.

3s The invention is based on the knowledge that the required doubling of the deflection energy at 110 ° contrary to the earlier view, does not lead to a proportional increase in power loss the line end tube leads.

-IO In order to achieve a deflection angle of 110 °, the impedance of the deflection coils was compared to approximately doubled over the 90 ° technique.

It was found that about 75% of the total magnetic energy in the deflection system is

Ί5 are saved. The increased inductance of the 1 ^ "deflection system is therefore decisive for the kickback circle. The transformer can therefore operate at 110 ° are designed with lower losses than at 90 °. Due to the substantial improvement in the Transformer efficiency is practically the power balance for the line end tube at 110 ° same as at 90 °.

Based on this knowledge, the invention relates to a line deflection circuit for 110 ° color image 5 tubes with a rectifier cascade circuit for high voltage generation and with a line output transformer, whose windings are arranged concentrically on one leg of a rectangular ferrite core and the number of turns of two transformer windings connected to ground, the outer connections of which form the transformer output for the line deflection coils connected in series, dimensioned differently are.

In this known line deflection circuit, the line deflection coils are expediently for the Deflection current connected in series, which makes the transformer particularly efficient.

3 '4

Furthermore, the circuit enables the booster capacitor and cathode of the Boosiier to see the cushion

equalization in east-west direction required sym- diode switched winding of the line output trans-

Metric modulation of the Hon / onlalablenkslromes formators.

with a blldfrequenten parabolic current in that in this embodiment the coupling

the working winding of one of the vertical saw tooth ratios from the eye to the booster capacitor

current-controlled transducer to the winding closed between Boo to the two neighboring ones

star capacitor and ground winding of the windings optimally, which is beneficial to the We

Transformer output for the line deflection coil efficiency of the transformer,

is connected in parallel. It is only a trans- An embodiment of the invention is shown in the pole

ductor is required, and the equalization is carried out in greater detail with the aid of a drawing,

freely and without disturbing repercussions on the high- Fig. 1 shows the basic circuit of the crfin-

tension. A modulation of the high voltage occurs formation-essential elements of a line deflection scarf

namely, although high voltage and deflection voltage.

voltage are firmly coupled via the transformer. In Fig. 2 the winding distribution of a line

not because the parallel connection of the transformer π output transformer according to the invention · im

duct inductance is shown at the same time as a compensation section.

tion effect occurs, which is due to a reduction in the In Fig. 1 with I is a line output transforma-

Kickback time is based. called tor, which has two windings 2, 3.

The invention is based on the object, for the connection point of which is grounded and the external

this circuit has a line output transformer 20 i3ere connections the transformer output for the

to find the required symmetrical feed-in deflection coil connected in series!) 4, 5. At

Solution of the corner convergence currents in the deflection coil one of these connections is via a booster con

len made possible. For this purpose, the feed point of this capacitor 6 must be connected to the booster winding 7.

Currents must be free of horizontal impulses. the other end to the cathode of the booster diode

The object is achieved according to the invention in that 25 8 is connected. The booster winding 7 closes that the number of turns with the Boosterkonden- a partial winding 9, the end of which with the Sator connected winding of the transformer-off anode of the line end tube 10 is connected. From dieganges for the line deflection coils is smaller than this anode connection leads to a further capacitance * Number of turns of the other winding of the transformer arm executed winding 11 in which the return gate output for the line deflection coils, so that the voltage is stepped up to an off Dio transformer output during the line run 'the rectifier and capacitors built up rectifier kasmassymmelrisch is. Cad circuit 12 to generate the required

The one for the symmetrical infeed of the dynamic high voltage.

see corner convergence currents required sym- Also, the line output transformer has

Irish interpretation of the deflection circuit is so by 35 1 additional windings 13, 14, which are used to generate

different dimensioning of the number of turns of auxiliary pulse voltages are used. Between the Ka

two transformer windings achieved. There is a capacitor under the ground of the booster diode 8 and ground

sesymmetry is to be understood that there is provided at both gate 15, which determines the return time.

Connections of the transformer output to a small internal resistance of the high voltage

To achieve the same trace voltage in relation to ground, the capacity must do this

will. A small asymmetry during the capacitor can be made as large as possible because

of the line return must be accepted, because from this a substantial part of the peak charging current

the corner convergence currents are only drawn during the row for the cascade. About the response time

are needed there. To keep it constant, the increase in capa

The connection linked to the booster current -15 by reducing the transformer inductance

of the transformer output can be compensated for the line deflection. With decreasing domestic

coiling is for the fed-in corner currents, low-ohmic inductance, and increasing transformer losses

less than the other connection. This will not allow any increase in capacity.

duly balanced in that the win The outer connections of the windings 2 and 3

connection number of the connected to the booster capacitor 50 are each with one of the for the deflection current in

NEN winding of the transformer output for the series-connected deflection coils 4 and 5 respectively.

Line deflection coils is smaller than the number of turns facing away from the line output transformer

the other winding of the transformer output ends of the deflection coils are by means of a condenser

for the / line deflection coils. gate 16 bridged, which is used to correct the so-called

This results in the 55th tangent error of the sawtooth current for the Hori-EMF without additional components which is not connected to the booster capacitor for deflection. This tangent correction denen Winding of the transformer output in the supply. Capacitor 16 is a balun transformer equal to the other winding increased so far that formed throttle 17 or possibly a Gebeide Connections of the transformer output are connected in parallel to the synchronous transformer, at their Corner convergence flow during the line trace 60 or its center tap 18 a corner convergence Oppose the same internal resistance. nerator 19 is connected. Because the number of turns

A further improvement of the symmetry of the off »2 of the winding 2 according to the invention by a sol-

steering circle is obtained in a further development the Eren amount is greater than the number of turns n _} the

found in that the axial winding width of the winding 3, that the caused by the booster current

The winding connected to the booster capacitor 65 slight asymmetry at the injection point removed

ner than the winding width that is arranged underneath, the additional current _{/] 9 is}

For the other transfer run in the deflection circuit, equal parts to the deflection coils 4 and 5

mator winding and the above arranged, between. The impedance of the choke is

set current is very small, while it is so large for the deflection current that the deflection current does not pass the throttle 17, but instead flows through the correction capacitor 16.

Furthermore, FIG. 1 a passive correction circuit with a transductor, its working winding 20 is connected in parallel to the transformer winding 3, and its control winding 21 from the vertical deflection current 22 is traversed. The corrective effect, which essentially depends on the dimensioning or the properties of the transducer used, can be determined by means of a potentiometer 23 influence within certain limits that the control winding is connected in parallel.

Particular advantages of the correction circuit shown here are that the transductor only is due to half the deflection voltage and its dimensioning and isolation are thereby simple, and that due to the connection of the winding 3 with the booster current still achieves a symmetrical modulation will. The repercussions on the control voltages for image width and high voltage stabilization are negligibly small.

F i g. 2 shows a winding former 24 on which the windings of the line output transformer are concentric are arranged. The reference symbols for the layers of the individual partial windings are the same as in Fig. 1. With 25 are intermediate layers or cover layers made of insulating material. The lower compared to the neighboring windings 2 and 7 Winding width of the winding 3, through which a uniform magnetic coupling of the winding 3 is achieved for the windings 2 and 7 can be clearly seen in the drawing.

In a line output transformer according to the invention, the winding shown in FIG. 2 is seated one leg of a rectangular ίο ferrite core, not shown, which in a known manner consists of two U-shaped Halves is put together. Between the abutting end faces of the U-shaped An air gap is established between the core halves by inserting hard paper disks. The dimensioning π of the air gap is an important parameter for the transformer losses that occur when the air gap is reduced get smaller.

A very good image quality was found in an inventive Line deflection circuit achieved with a line output transformer whose number of turns for the individual windings is as follows had:

n ₂ = 120
n ₃ = 112

n ₇ = 414

n, = 124
n _n = 144
Air gap = 0.5 mm

1 sheet of drawings

Claims (2)

Patent claims: 1. Line deflection circuit for I IO ° -Farbbiklröhren with a rectifier cascade circuit for high voltage generation and with a cell output transformer, the windings of which are arranged concentrically on one leg of a rectangular ferrite core, and the number of turns of two transformer windings with their connection point at ground, the outer connections of which the transformer -Output for the series-connected line deflection coils, are dimensioned differently, characterized in that the number of turns (/? ₃ ) of the winding (3) connected to the booster capacitor (6) of the transformer output for the line deflection coils (4, 5) is smaller is than the number of turns (/? ₂ ) of the other winding (2) of the transformer output for the line deflection coils (4, 5), so that the transformer output is mass symmetrical during the line trace. 2. Line deflection circuit according to claim 1, characterized in that the axial winding width tier with the booster capacitor (6) connected winding (3) is smaller than the winding width of the other transformer winding (2) and located underneath in the deflection circuit the one above it, connected between the booster capacitor (6) and the cathode of the booster diode (8) Winding (7) of the line output transformer.