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Has anyone ever added a dimmer to a LED clock? Answered

Hi, Can anyone provide some insight into adding a dimmer to an LED clock radio?

I've tried out several and the things are all way too bright for my bedroom. I'm a decent soldering tech and I'm very comfy voiding warranties.

I didn't post particulars about a clock as I have several. I mainly want to know if anyone has done something similar before I start opened cases.


The potentiometer idea from Downunder35m would be my choice. Selection of the resistance range is important otherwise you can shorten the life of the LED drastically.

Thanks, Bookgity!

A real dimmer seems like such a perfect feature to brag on. Some marketer missed the boat.

i have dark film which was sold for car windows over my computer screen. tho i dont mind voiding a warrantee, the path of least resistance is sometimes nice. easier to undo, too.

Sure but the film can affect the clarity of the displayed time, tried it and did not like it.

Plus changing the resistor gives much longer lifetime for the LED.

For some weird reason all the projector clocks I got for repairs faile because the LED was driven at max ratings - good to see in daylight, bad for the lifetime and too bright at night.

I replaced my LED yearsago with super bright red one and added a higher resistor in series.

The original burnt out after just a year.

If your's is made as cheap as mine you will find a resistor attached to the LED, simply replace it with a bigger one.

Let's say you got a 27Ohm resistor now, try a 330Ohm resistor.

You can also use a potentiometer in the range of the orignal resistor (1kOhm should be good) and make it dimmable, just needs some hotglue and a hole in the side.