Vertical Hold won't roll the pix down
 

Where is the problem, in what circuit, the Vert. osc or Vert. output, when the vertical hold works but won't roll the picture down? this is on an older B&W RCA KCS38.

Thanks, John

The vertical oscillator frequency is probably not right...have you replaced any old capacitors? Does it have a steady picture? If the control will only move it in one direction the oscillator is too far off the center 60 hz frequency.

If your picture has good height and linearty I'd suspect a problem in the oscillator
circuit.