• SubArcticTundra@lemmy.mlOP
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    2 hours ago

    4W is impressive given how high voltages are needed for any CRT. I suppose the current must be minuscule to compensate?

    • ChaoticNeutralCzech@feddit.org
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      1 hour ago

      The anode current for such a small screen area is pretty low. The flyback also provides a few hundred V to 1 kV for various grids like focus and brightness of the electron gun. Since they all use voltages adjustable in different ranges, a single series of resistors and potentiometers is employed as an adjustable potential divider, consuming usually less than 1 mA (1 W).

      With such small sets (or ancient vacuum tube ones), the power draw of the electronics driving the deflection coils is also considerable. I’d guess about 2 W for the CRT heater, 1 W for the HV, 1 W for the sync, amplification and deflection.