Using a Common mode Choke (differential) as a joule thief transformer (working)

Almost any switch mode power supply has one of these chokes for noise suppression.  The type pictured below is the type that has been tested working.

The prewound choke Coil has even windings on both sides and uses many turns of thick wire around a ferrite core.
Using the standard Joule Thief configuration, it has been tested with a BD139 transistor, 1.4K Ohm Feedback Resistor and a Blue LED.
Starts up easily at 0.6V DC. and is much brighter than the standard joule thief at 1.5 Volts.

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Acer AL922 19 inch LCD Monitor Repair [BadCap]

Another case of the bad caps.  Would not switch on or just for a second.  The monitor is powered by a 12V 5A switchmode mains adapter.

Opening it was easy, remove the two screws under the rubber feet and pry the case open from the other side, where the adapter cord comes out.

The bad cap was the big mains one, puffy and leaking.

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