|
I'm sure the photos of the two traces are from the two grids. The first section of the tube has the grid connected to the oscillator. The waveform is amplified and inverted in the first section. A portion of the signal from the first plate (inverted as compared to the grid of that section) is fed to the grid of the second section. That is the purpose of the C57, C142, R117, etc. Those components attenuate the signal from the plate of the first section by an amount equal to the gain of the first section, so thr proper amplitude is fed to the grid of the second section.
The second section of the tube amplifies and inverts that waveform. So, the waveforms supplied to the CRT defectin plates are inverted.
The inversion process take place as Steve K describes it.
|