Replacing The B+ Coil With A Wire?
I believe CRT Monitor repairers came across B+ coil in the circuit. The function of the B+ circuit (boost circuit) is to boost the Dc voltage from the SMPS so that it can be channeled it to the flyback transformer primary winding. The B+ voltage is required to support different resolution in the Monitor. That means the B+ voltage will vary if the display resolution change. If the B+ coil burnt the only way is to replace it with a new coil or you rewind it on your own. The question is can we replace the Burnt B+ coil with a single wire?
The answer is No because the function between a coil and a wire is different. The function of the B+ coil is to store current and the wire is to act as a path for the Dc voltage to flow through. In other words, without B+ coil there will be no current be transferred to the B+ capacitor in the B+ circuit thus the voltage can’t be boosted. If the B+ voltage is not boosted then the flyback primary winding would not get what it want (flyback needs a higher DC voltage) thus the high voltage generated would be low-may in the range from 12 to 15 Kvdc only.
Because of this situation, the display will become small vertically (may be 6 to 8 inches wide) and in some cases the display curve inwards (squeezed in the right and left side). Hope that in the future, if any B+ coil burn, please do not put a wire to replace it.