Back to board washing for a moment

On Tue, 8 Jan 2002, Adrian Graham wrote: If the flyback is sealed, it shouldn't be a problem. Most modern flybacks are not 100% sealed, and have a couple of variable resistors on one side. Typically, the flyback is installed after washing when these boards are manufactured. You will often find flux on the pins for these types of parts, since the board will have already been defluxed before the washing. I'm not sure I'd wash such a board with the flyback installed, since they are usually easy to remove, and often their solder joints need to be redone anyway. Often when the flybacks are installed at the factory, the joint is not allowed enough time to heat properly, so the solder does not bond properly to the pin or pad. Over time, these solder joints are prone to failures, which cause lots of intermittent problems in monitors and TVs. Flybacks are also very expensive to replace, and it's often difficult or impossible to find an exact replacement. Make sure you properly discharge the CRT and other caps in the HV section before disconnecting the anode lead from the CRT. You can find some basic service and safety information on the sci.electronics.repair FAQ located here: http://www.repairfaq.org/ -Toth