Old classical oscilloscopes had a CRT which used a relatively slow beam, two pairs of deflection plates and a phosphor screen opposite the electron gun. When a sawtooth waveform is applied to the horizontal deflection plates and a test signal is applied to the vertical plates, a waveform was drawn on the phospor screen. The electron beam was blocked at the scanning sawtooth waveform vertical asymptote. This seemingly simple arrangement produced the basis of an oscilloscope.
Unlike the above, modern oscilloscopes are computers with high speed ADCs connected to them as peripherals or integrated on the same board. Technically, they are much more complex.
Can the rows be addressed without digital processing? Digital processing would require an ADC
and additional processing to address the liquid crystal rows.
Is it possible to emulate without digital processing a CRT suitable for an oscilloscope using a liquid crystal matrix from, say, an old monitor?
The liquid crystal has a time delay when it is activated like a phosphor screen. The columns can be addressed using a ring counter.
OOPs!
Using a ring counter is digital processing although not complex like using a CPU.
Unlike the above, modern oscilloscopes are computers with high speed ADCs connected to them as peripherals or integrated on the same board. Technically, they are much more complex.
Can the rows be addressed without digital processing? Digital processing would require an ADC
and additional processing to address the liquid crystal rows.
Is it possible to emulate without digital processing a CRT suitable for an oscilloscope using a liquid crystal matrix from, say, an old monitor?
The liquid crystal has a time delay when it is activated like a phosphor screen. The columns can be addressed using a ring counter.
OOPs!
Using a ring counter is digital processing although not complex like using a CPU.
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No: what you want to achive is not possible, at least not with a modern LCD panel, because the processing board inside the panel only accepts a digital serial bus (usually EDP). To get access to individual row and column signals, you need to find a older, less integrated LCD panel with separate timing board and then you need to dismantle it and figure out the undocumented connections of the flexible PCBs with row/column drivers mounted on top that came out from the panel sides.
Thank you for replying. So, it is more possible to use an old CRT based monitor tube and try to use a slow electron beam with external deflection plates.
