Matsushita Electric Industrial Co., Ltd.

Seiji Fujisawa

Toshihide Tanaka

Susumu Ide

Toshitaka Yukumoto

Toru Michioka

In a convergence device for a three primary-color projection type color television system with three cathode-ray tubes, it is known to use two separate cores respectively for dynamic and static convergence correction. In the present invention a single core is used and the core is provided with eight pole pieces aligned along the vertical, horizontal and two diagonal axes, each pole piece having a winding therearound. The vertically and horizontally aligned pole pieces are used to correct horizontal and vertical dynamic convergence respectively. The diagonally aligned pole pieces are used for both the horizontal and vertical static convergence correction by producing magnetic fields horizontally and vertically. The construction is much simpler than the prior art, and the correction of dynamic and static convergence which is required as a result of the difference in incident angles between electron beams projected on a screen can be easily attained.

Convergence device for projection type color television system

A television receiver comprising a first printed circuit board having a helical resonator filter, an adjacent channel trap circuit and an impedance converter circuit for providing a reduced output impedance, the first printed circuit board being secured to the tuner casing, and a second printed circuit board having first and subsequent i-f amplifier stages, the two printed circuit boards being connected to each other, whereby good skirt characteristics can be simply obtained. Also, no overall adjustment is required but the tuner and i-f amplifier may be adjusted separately, thus providing improved serviceability.

Television receiver I. F. circuitry

A broad-band signal transmitting device including a signal transmitting transformer of the primary to secondary turn ratio 1 : N, comprising a first circuit for expanding the transmission band to low frequencies by decreasing the impedance as well as by decreasing the gain for the signal component in the primary circuit of the transmission transformer, a second circuit connected with the output side of the transmission transformer having an impedance larger than N.sup.2 times of the impedance of the primary side and smaller than the impedance exhibited by the stray capacitance of the secondary side at the upper limit of the transmission band, an amplifier for recovering the gain drop in the first circuit, and a low frequency compensating circuit for compensating the lack of low frequency transmission characteristic due to the transmission transformer.

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Ikoma, Japan

Seiji Fujisawa