Zenith Chromacolor J free download

File name Zenith Chromacolor J TV chassis 1977.pdf

Zenith Color TV for 1978 We continue with our review of changes, improvements and innovations in color television for 1978. This month-the `updating' of the Zenith "J" line. By Don W. Mason Fig. 1-Modules used in vertical circuitry in the Zenith J line of color TV. Top four modules are DC -coupled, and bottom three are AC -coupled modules. As with most other TV set manu- modules are completely inter- facturers this year, Zenith is "up- changeable, but the AC -coupled dating its color television line for modules are not, and must be used 1978-refining the circuitry and as intended with specific chassis adding new customer features- and deflection angle receivers. rather than introducing new chas- Actually, the AC -coupled mod- sis and new models. (Zenith has ules can be interchanged for ser- introduced a new videocassette vicing purposes, but should not be recorder and a new black -and - left in the receiver for normal op- white TV chassis, however, as ad- eration as a poor linearity condi- ditions to their 1978 product line.) tion will exist. The improvements in circuitry A schematic of AC -coupled ver- are concentrated on the "J" line of tical module 9-120-01A is pro- Zenith color chassis. Circuits in- vided in Fig. 2. Whenever servic- volved are: vertical, horizontal, ing for vertical problems involving high voltage multiplier, low level this module, the emitter resistors, luminance, video output, IF and RX213 and RX214, of the output the tuner. amplifiers should be checked for an open condition. And, if resistor The Vertical Modules RX728 has opened, do not replace The seven different modules the module before checking for a (Fig. 1) used in the vertical circuit short or other fault in the output