01-11-2019, 11:04 AM
Line drive to the PL38 is critical so the transistion between reclaimed energy from the boost diode and the sawtooth waveform from the oscillator must be correctly adjusted.
Have you replaced the 0.01microfarad coupling capacitor between the line oscillator and the grid of the output valve? C17 in the Bush service manual.
Also check the value of the anode load resistor of the line oscillator valve, R17, 820Kohms.
More infprmation, line drive trimmer adjustment.
Horizontal drive: Adjust TC1 for maximum width and maximum EHT, reducing the picture-width control as required. Increase brightness to provide an over brilliant picture, and if a vertical white bar is apparent down the picture adjust TC1 (screwed in) until the bar disappears. if there is difficulty in eliminating the bar, adjust the horizontal form control at the same time.
Geordie McBoyne.
Have you replaced the 0.01microfarad coupling capacitor between the line oscillator and the grid of the output valve? C17 in the Bush service manual.
Also check the value of the anode load resistor of the line oscillator valve, R17, 820Kohms.
More infprmation, line drive trimmer adjustment.
Horizontal drive: Adjust TC1 for maximum width and maximum EHT, reducing the picture-width control as required. Increase brightness to provide an over brilliant picture, and if a vertical white bar is apparent down the picture adjust TC1 (screwed in) until the bar disappears. if there is difficulty in eliminating the bar, adjust the horizontal form control at the same time.
Geordie McBoyne.
