Early Television

Vintage Television Sets and Colour Television Sets from the Dawn of Television until Now

Echard Etzold's Site

Philips K8D

Colour television:

Philips "Goya 110L (Chassis K8D)"

1972

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[Text in deutsch]

Philips K8D


The Philips Goya 110L belongs to the third generation of hybrid colour tv sets, and it was the first colour tv set with a 110° deflection picture tube on the continent. The K8 chassis has still 15 valves. The total power consumption is 400 watts due to the higher deflection currents in comparison with 90° deflection colour tv sets. No other colour tv set, which was sold in Germany, has such a high total power consumption.

Philips K8D Philips K8D

The K8 chassis is a further development of the K7 and K6 chassis. Tuner, IF and chroma circuits are solid state. The colour difference output unit, video output and sound are fitted with valves like in the K7 chassis. The large heat from the valves and the high power resistors burned the board of the chassis in the upper part.

Philips K8D Philips K8D

The picture tube with 110° deflection is much shorter than a 66 cm. picture tube with 90° deflection. As a result, the whole set has a shorter depth than the 90° colour tv sets before. Deflection circuits and convergence circuits are more complex due to the higher deflection angle. The convergence board is placed behind a door on the right side of the set (viewed in front of the set). The convergence needs active parts with high-wattage transistors here in comparison to the total passive circuits in 90° colour tv sets to generate enough signal power for the correct geometry.

Philips K8D Philips K8D

The A66-120X was the first 110° deflection delta shadow mask colour picture tube. The iron-brass cover for shielding geomagnetic effects is placed now in the inside of the picture tube. Philips used colour difference concept for the colour output units. The PL 802 is for luminance output, three PCF 200 are for colour difference signal output. White balance is realized with three VDRs on the crt board. The white balance use the black level niveau as a reference for white balance control.

Philips K8D Philips K8D

In the K6 and K7 chassis, one line output transformer was used for deflection and EHT. This transformer was driven by a PL 509 and a PL 504. In the K8 chassis, two transformers are used, one for deflection, and another one for EHT. Both transformers are driven by a PL 519 and a PY 500A each. EHT stabilizing is realized with a GY 501 and a PD 510 as a shunt regulator like in the K7 and the K6 chassis.

Philips K8D Philips K8D

The picture tube is still strong on all three cathodes with more than 1 mA beam current.

Schematics

Schemanic diagrams

Valves

PCL86, 3 x PCF200, PL802, PCF802, PCH200, PL508, 2 x PL519, 2 x PY500A, GY501, PD510, A66-140X.

Photos: © Eckhard Etzold, 2007

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