J
Jeff Wisnia
Guest
I'm interested in finding out what the circuit inside a GE white LED
"night light" looks like, but I'd prefer not to have to bust open one of
the two we use in out bedroom and bathroom to find out.
I'm guesing that it may be just the LED, with a diode across it and a
series cap, and maybe a little series resistance to absorb transients.
But perhaps it's something entirely different.
The reason I'm asking is to satisfy my curiousity about what's happening
to the night light in our bathroom. It is plugged into an outlet fed by
the same circuit as the bathroom's exhaust fan. Fan operation is
controlled by a spring driven wind up timer which AFAIK provides just
mechanical switching of the circuit it controls.
The fan is driven by a shaded pole motor which probably draws far less
than an amp when it's running.
What's bugging me is that *sometimes* as I turn the fan on the
nightlight blinks OFF for a fraction of a second, and once I saw it do
that when the timer switch clicked off. The LED looks like it's going
dark for perhaps 1/4 second, but definitely long enough to notice.
I tried whacking the wall in the area of the switch and the outlet to
see if a "loose disconnection" might be the culprit, but I couldn't get
the LED to blink off by doing that.
I has all the symptoms of switching the current to the motor through a
set of mechanical contacts causing a transient which charges a capacitor
in the night light in a direction that turns the LED off until things
equalize again.
My curious mind wants to know wot's happening...
Thanks guys,
Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
http://home.comcast.net/~jwisnia18/jeff/
"Truth exists; only falsehood has to be invented."
"night light" looks like, but I'd prefer not to have to bust open one of
the two we use in out bedroom and bathroom to find out.
I'm guesing that it may be just the LED, with a diode across it and a
series cap, and maybe a little series resistance to absorb transients.
But perhaps it's something entirely different.
The reason I'm asking is to satisfy my curiousity about what's happening
to the night light in our bathroom. It is plugged into an outlet fed by
the same circuit as the bathroom's exhaust fan. Fan operation is
controlled by a spring driven wind up timer which AFAIK provides just
mechanical switching of the circuit it controls.
The fan is driven by a shaded pole motor which probably draws far less
than an amp when it's running.
What's bugging me is that *sometimes* as I turn the fan on the
nightlight blinks OFF for a fraction of a second, and once I saw it do
that when the timer switch clicked off. The LED looks like it's going
dark for perhaps 1/4 second, but definitely long enough to notice.
I tried whacking the wall in the area of the switch and the outlet to
see if a "loose disconnection" might be the culprit, but I couldn't get
the LED to blink off by doing that.
I has all the symptoms of switching the current to the motor through a
set of mechanical contacts causing a transient which charges a capacitor
in the night light in a direction that turns the LED off until things
equalize again.
My curious mind wants to know wot's happening...
Thanks guys,
Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
http://home.comcast.net/~jwisnia18/jeff/
"Truth exists; only falsehood has to be invented."