RCA F31317 lost blue in picture.
this symptom is characterised by the loss of one or two primary colours. this symptom can be classified into three cases: 1) loss of red colour, 2) loss of colour blue,3) loss of green color. this symptom may be caused by a trouble in the colour demodulator, in the color amplifier or in the colour subtraction amplifier circuit. in your case loss of blue colour. this is a very complicated problem that you need some special test equipment like oscilloscope and color pattern generator in order to trace the signal. tune the receiver to a color broadcast station(a colour bar generator can be used to transmit a colour signal to the set). check the Z-axis demodulator, z-axis amplifier and the B-Y output circuit for the chroma signal. observe the signal process with an oscilloscope. if the color signal is not present use a VOM to locate the defective component in any of the above circuits. check the transistors and the resistors in the collector circuit. good luck!
Feb 14, 2007 |
RCA F31317 31" TV