Author Topic: NightLight  (Read 1687 times)

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Offline rossw

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« on: June 27, 2013, 09:33:53 pm »
This is just to prove to Tom that I can (and do) do some horrible work too!

This was a nightlight I was given some time ago. It used to have a little 4" or 6" fluro tube in it, but it was wired in some oddball horrible way that sort of used it like a cold-cathode tube. Never worked very well.

It had been in operation for about a week recently for an unwell pet. Yesterday morning it was dark...
Tube was all black and honestly, I couldn't see the future in replacing it. Instead, I grabbed some 10mm white LEDs, ripped out the old innards of this thing, soldered the LEDs in a direct two series pairs of back-to-back diodes, put a 1K resistor in series and an 0.1uF capacitor across the 240V AC...

The old one used to draw about 4 watts. The new one - apart from looking a bit ugly (4 bright spots instead of a large, evenly illuminated panel), and being slightly dimmer - barely registers on my meter, showing a powerfactor of around 0.03 and a power draw of between 0 and 0.2 watts.

Offline oztules

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Re: NightLight
« Reply #1 on: June 28, 2013, 12:51:12 am »
even if Tom does not like it.... I do...

Flinders Island...... Australia

Offline ghurd

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Re: NightLight
« Reply #2 on: July 25, 2013, 01:33:55 pm »
Looks fine to me.  Everything always looks better with the cover on!

Might get a bit more light out of it with some of that shiney AL tape over the grey plastic area.

If you get extra bored and feel the need to use that fancy meter again, I would be curious how it works with 3 pairs of LEDs, both in brightness and power.