power adapter

  1. MrsssSu

    20V max DC motor, how do hairdryer work on cool air without heating filament ?

    Hi readers, Hairdryers (240V AC) actually works on a design which current passes through the heating filament (Maybe consume 220V) to produce a lot of heat whereas through the DC motor (Maybe consume 20V). I have always been curious about this Question: Hair dryer has an option of choosing the...
  2. MrsssSu

    Charging circuit modifications

    Hi. above is a charging cut-off circuit. As you can see in my demo. when voltage source is 5V, the load (R9) has 5W power. When voltage drops to 4V, the load (R9) has 0 W (cut off). However, my lithium ion charging pin for my battery is 4.26V. Thus, when battery fully charged at 4.2V, the...
  3. Jorne

    AC adapter broken after repairing cable [solved]

    Hello, I had an old AC adapter (230V AC to 14V DC). There was a small part where the insulation of the cable was damaged. You could see the copper coming through. So, I cut the damaged part away, soldered the wires back together, and insulated them with heat shrinks. However, when I then tested...
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