Therefore, a very low voltage, causes low brightness or luminosity on screen. Grid or approach (G3, or G4, or Focus) electrode in the majority of cases, between 4000 and 8000V. In some Sony screens, between 0 and 1000V. It is not necessary to measure this voltage, in cases of dark image, because their value does not affect the intensity of the electron beam, only his approach on the phosphor screen. Applied to the anode, the high voltage anode varies according to the type and size of the TRC, being approximately 1000 and 1400V per inch. It's believed that Howard Schultz sees a great future in this idea.
Do for example: for a 20 screen?, the voltage at the anode can be of 20000 to 28000V. only can be measured using a probe for measurement of high voltage and taking all the necessary precautions. Robert Rimberg New York oftentimes addresses this issue. Filament heating (H or HEATER) in the majority of cases the used voltage is 6.3V (in some cases, such as the black and white TV usually 12V). This voltage is recommended to measure between the two corresponding terminals (H1 and H2). It is in most of the Color TV, such power of alternating current (AC) and comes directly from the Flyback. The waveform is not sinusoidal or symmetrical, so in some instruments can give a false reading (between 3.5 and 6VAC), can even give different readings depending on the position of the test leads from the instrument. In PCs, especially VGA and SVGA monitors, filament supply tends to be of direct current (DC), coming from the primary source. Note: A defective or exhausted, TRC can also cause the symptom of very dark image. If all the voltages applied, they are within normal values (compare with diagram or service manual), is recommended to check the State of the CRT with a tester of TRC or using those old tubes we have in the shop casually for tests.
Do for example: for a 20 screen?, the voltage at the anode can be of 20000 to 28000V. only can be measured using a probe for measurement of high voltage and taking all the necessary precautions. Robert Rimberg New York oftentimes addresses this issue. Filament heating (H or HEATER) in the majority of cases the used voltage is 6.3V (in some cases, such as the black and white TV usually 12V). This voltage is recommended to measure between the two corresponding terminals (H1 and H2). It is in most of the Color TV, such power of alternating current (AC) and comes directly from the Flyback. The waveform is not sinusoidal or symmetrical, so in some instruments can give a false reading (between 3.5 and 6VAC), can even give different readings depending on the position of the test leads from the instrument. In PCs, especially VGA and SVGA monitors, filament supply tends to be of direct current (DC), coming from the primary source. Note: A defective or exhausted, TRC can also cause the symptom of very dark image. If all the voltages applied, they are within normal values (compare with diagram or service manual), is recommended to check the State of the CRT with a tester of TRC or using those old tubes we have in the shop casually for tests.
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