What happens to the screen of a crt TV if 1) 180vol are missing
Good afternoon; In fact, it may be the case that the filament voltage and 180/200 Volts are absent due to the service output of the fusers that protect their path. The voltage of 180 to 200 volts for the RGB transistors that are in the small circuit board in the TRC if it is absent for anything, either because a resistor was opened or because it is poorly filtered is the: White screen with lines of stroke.
This voltage can only be "seen" by measuring after the cathode of the diode that rectifies it. (Actually in conjunction with the capacitor that filters it) ... Another fault that can cause the absence or poor filtration of this voltage is: A lateral "shadow" on the screen, this fault is recurrent in old Goldstar TVs, now called LG .
Continuing with failures of this tension, if it comes from the source, the fault is oblique lines on the screen. This fault is seen in televisions with Chinese chassis, one would think that it is the Jungle, but it is not badly filtered.
Now if it is the case to be absent the video tension, (As far as I know it cannot be measured with a tester, but this is my own assessment) You measure to see if your tester can measure it, you are supposed to throw a reading of 6 volts in DC or DC Continuous Current ... I observe it in an oscilloscope, and it measures approximately 27 Volts pp.
In general, you only need to see behind the neck of the CRT and verify the presence of filament luster; Its absence causes the characteristic to fail: I have audio but no image, a client would say ... Causes false welding or in poor condition, cut tracks, cut wires, open resistors, which is unusual, and if they find it open It can get complicated.
