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Why weren't electrostatic deflection CRT's more popular for TVs and monitors?
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ELS122:
Isn't it cheaper, more compact, and ever so slightly more energy efficient to use electrostatic deflection?
Why didn't more TV's use electrostatic deflection? was it problematic to get enough deflection as the screen size grew?
Berni:
Electrostatic deflection is weaker. So it involves a lot of voltage to drive the deflection plates while not providing as much deflection, so the CRT ends up being pretty long. Not a problem for a scope but a big problem if you are making a 35 inch TV.

Magnetic deflection is plenty fast enough too. You can do 1080p like resolutions on a CRT just fine. We didn't have TV broadcasts that high resolution back then and computers typically ran at around 1024x768 back then. So we didn't need more speed anyway.

The higher acceleration voltages of color CRTs also appeal to magnetic deflection, since electrostatic plates have less time to do the deflection with faster electrons.

EDIT: Oh and you are getting your electrostatic deflection back in the form of DLP chips and micromirror scanned laser projectors
TimFox:
Yes, deflection angle.
Consider scaling up a 5CP1 CRO CRT from a 5-inch envelope up to even a 21-inch envelope.
Early TVs mounted the CRT vertically with a viewing mirror for the relatively small screen.
N2IXK:
Because as screen size/deflection angle increases, so does the voltage needed for full deflection.

The early electrostatic deflection TV sets were mostly 7" CRTs, and they needed 3-400V of drive to sweep the beam across the screen, The amount of voltage to get full deflection on a 20"-25" CRT would be MUCH higher. Magnetic deflection is used to eliminate the need for high voltage deflection amplifiers.

The main advantage of electrostatic deflection is high deflection bandwidth, which is important in an oscilloscope CRT, but MUCH less important in a television application, where raster scanning is done at relatively low, fixed frequencies.  The deflection amplifiers to drive a magnetic deflection yoke are simpler and lower cost, and the horizontal amplifier can be made to double as the driver for the CRT accelerating voltage power supply. The early electrostatic TVs needed a separate HV power supply to provide the accelerating voltage for the CRT.
TimFox:
By the time of my RCA RC-24 Receiving Tube Manual (1965), magnetic-deflection monochrome CRTs could do 110 to 114 degrees total deflection.
Note that the energy used for the higher-speed horizontal deflection was not wasted:
The linear increase in current during the horizontal scan was done by switching a low-resistance tube in series with the horizontal coil and the DC supply:  to first order, dI/dt = V/L.
During re-trace, the current collapsed into a "damping diode", and the induced voltage went into the high-voltage rectifier tube from a higher-voltage tap on the deflection transformer to generate the CRT voltage.
Hence, the term "flyback" supply, still used for other purposes.
Later, as transistors entered TV sets, the flyback supply was used to generate the low voltage required for the solid-state circuits, avoiding a heavy power transformer.
Early TVs used plate-capped 6L6 variants (807, 6BG6), but later "sweep tubes" such as the 6DQ6 were designed for that service.

For both horizontal and vertical deflection in a periodic raster, the DC component of the deflection coil current is zero, so the waveforms can be transformer coupled.
The slower vertical waveform used an actual sawtooth power oscillator;  the controls for both horizontal and vertical "hold" and "linearity" required manual adjustment, and the drives for both were derived from the sync pulses extracted from the composite video waveform.
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