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Why I built this circuit.
I purchased a roll of 12 volt LEDs and find they operate from 5-7 volts to 14-16 volts.
A friend of mine needed light in his shower now that he's a bit older, so I built this circuit in a electrical box & mounted in his wall.
The box cover is a heatsink that fits the box, I mounted the bridge rectifier and the pot on this heatsink. Inside the box are the cap and transformer and all connection's to mains and LED's.
Description of the circuit.
With a 10k pot, This gives a very fine control over the voltage to the LEDs, by controlling the high voltage to the transformer the swing across the pot is 110+ volts. On the secondary side u only swing 10+ volts. So the moral of the story is, you have ten times the control in brightness on the primary side. If you tried to control the secondary side in the past and found a jump in brightness this is due to a wire wind pot and less voltage per wind.
If you move the pot to the primary side you will find the brightness will not jump as there is more voltage per wind.
I had lots of 10k pots in my box of goodies and very few 1k pots, a 1k pot on the secondary will act just like a 10k on the primary. The 1k pot uses smaller wire so u don't get the jump in brightness.
Using a pot on the input side of a transformer is dangerous unless, persecutions are adhered to --- be sure the pot can't make contact with you by using a plastic knob to adjust the shaft & the pot is rated for the voltage you are working with.
When buying part's for your project you have a chance to buy cheap or quality, cheep will work for lots of things.
Quality parts will outlast or project, and can be used for many things over decades making it cheep over time.
Keep the hobby alive and diy for success.
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