Where to buy tiny 16 volt door bell bulb?
Ahmed Rasheed
My door bell bulb that keeps the button visible in the night is burnt
out. Where can I get a replacement bulb? I couldn't find it in local
home depot on door bell section and couldn't find some one for help too.
Degerberg
>Where to buy tiny 16 volt door bell bulb?
Try a hobby shop or Radio Shack
Grandfather Bob(dege...@aol.com)
Modesty in the face of talent is hypocrisy.
Better honest arrogance than false modesty
paull
Ahmed Rasheed wrote
>My door bell bulb that keeps the button visible in the night is burnt
>out. Where can I get a replacement bulb? I couldn't find it in local
>home depot on door bell section and couldn't find some one for help too.
.......................................
Visit Radio Shack
Robert Hancock
You may just have to buy a new doorbell button.
--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from rhan...@nospamsk.sympatico.ca
Home Page: http://www.geocities.com/TimesSquare/Arcade/9967
Ahmed Rasheed wrote in message <351FBB...@galactose.mc.duke.edu>...
Frank Richichi
>My door bell bulb that keeps the button visible in the night is burnt
>out. Where can I get a replacement bulb? I couldn't find it in local
>home depot on door bell section and couldn't find some one for help too.
I had the same problem. The buld burned out after 7 years. I found
that is was easier to get a replacement button. Chances are the
mechanism is wearing out anyway. The dime sized button fit into the
brass face plate of the original button. Having said that, if I had
thought of Radio Shack as another poster suggested I would have done
that.
Frank Richichi
Clinical NetworX
frankrRE...@cnrx.com
John Hascall
Ahmed Rasheed <ras...@galactose.mc.duke.edu> wrote:
}My door bell bulb that keeps the button visible in the night is burnt
}out. Where can I get a replacement bulb? I couldn't find it in local
}home depot on door bell section and couldn't find some one for help too.
I used a tiny 12v bulb and resistor (in series) from radio shack
-- given the current draw of the bulb you can easily figure
the correct size resistor.
John
--
John Hascall, Software Engr. Shut up, be happy. The conveniences you
ISU Computation Center demanded are now mandatory. -Jello Biafra
mailto:jo...@iastate.edu
http://www.cc.iastate.edu/staff/systems/john/welcome.html <-- the usual crud
Don Klipstein
John Hascall (jo...@iastate.edu) wrote:
: I used a tiny 12v bulb and resistor (in series) from radio shack
: -- given the current draw of the bulb you can easily figure
: the correct size resistor.
You want a doorbell lightbulb to reliably last for a few decades, with a
decade being nearly 90,000 hours. Most 12 volt bulbs are rated to have
some usually shorter lifetime at 12 volts. Give the bulb 9 volts and on
paper, things should be fine. For good measure, give the 12 volt bulb 8
or maybe as little as 6 volts.
A 12 volt bulb of this sort usually draws about 80 percent of its rated
voltage at 8 volts and about 68-70 percent of its rated current at 6
volts. Use these figures to determine the dropping resistor, and figure
that the doorbell transformer probably delivers 110 percent of its rated
voltage to such a light load. Verify the voltage going to the bulb if you
have a multimeter.
So if you have a 16 volt transformer and you want to light a 12 volt 60
mA bulb with it, do this:
The transformer will probably supply 17.6 to 18 volts to a light load.
Suppose you want 8 volts across the bulb. You will use the resistor to
drop the difference, about 10 volts. At 8 volts, the 60 mA 12 volt bulb
will draw about 80 percent of rated current or about 48 mA. A 10 volt
drop divided by .048 amp is 208 ohms. The nearest common resistor value
is 220 ohms.
One more thing: The 10 volt drop times .048 amp means .48 watt of power
being dissipated in the resistor. You can get 220 ohm 1/2 watt resistors
at Radio Shack, but this is really pushing the limit of the resistor. You
would then want two 100 ohm 1/2 watt resistors in series, which may be
hard to cram into a doorbell button.
So maybe get the 20 mA 12 volt bulb from Radio Shack and use a 680 ohm
resistor. But this one will be dim. Now it seems more feasible to get a
28 volt bulb, but the minimum order and/or shipping cost requirements of
most places selling these will make the cost of a 28 volt bulb higher than
the cost of an entire lighted doorbell button.
If you really want to do some work and replace the light in an
illuminated doorbell button, try this: Get two ultrabright LEDs of
whatever color you want. I think Radio Shack's 276-307 ultrabright red
ones would be nice. Put them in parallel with each other, in opposite
directions. Put that pair in series with a 1K-ohm (one thousand ohm) 1/2
watt resistor. Please note that the main purpose of doing this is to have
an illuminated doorbell with your own color and as unique as possible.
Relamping a doorbell button could be tricky and may not cost less than a
new illuminated button.
- Don Klipstein (d...@misty.com)
http://www.misty.com/~don/led.html (my bright LED page)
http://www.misty.com/~don/blueled.html (my blue LED page)