I can't seem to find a 9 V grain of wheat incandescent bulb anywhere.
Looking for something small ( about 1/4"- 1/2" size), best with leads either
radial or axial, but will settle for screw or bayonet connections. The
application is for VU meter lighting in a large console, which I'm also
rebuilding the metal frame (metalwork content).
cheers
T.Alan
Ah, no. That isn't the way it goes. The guy apparently has a 9V source and
wants a bulb to run on that. A zener will take the 12V bulb and allow it to
run on a 15V source.
--
Why isn't there an Ozone Hole at the NORTH Pole?
Start by trying a 12V bulb. It will run a bit yellow and not put out as
much power but it will run for basically forever at that voltage.
If you really want full brightness in a nice white light, take a 1.5V bulb
and run a resistor and pair of diodes (in series) in parallel to the bulb to
insure that the voltage doesn't go too high. A 3V bulb is avialble also but
aren't as common.
--
Why isn't there an Ozone Hole at the NORTH Pole?
How do you know you need a 9 volt lamp? Is this specified or are you
assuming this from the voltage you are measuring? It could well be that
the original design was to use a 12 volt lamp on 9 volts to give a
softer light and to give an extended bulb life.
Chuck P.
If you're tearing it apart anyway I'd suggest converting it to LED
lighting so you don't have to tear it apart again in the future to
replace burnt out bulbs. White LED have become quite cheap (~$1-$2
depending on output) so even if you're talking a 32 input board the
hassle of having to replace them in the future outweighs the cost
difference. It also gives you the option of using different colors if
you want, say one color for inputs another for mains another for subs...
Pete C.
"T.Alan Kraus" wrote:
I think the LED suggestions are good.
But if you must use grain of wheat/rice lamps, model railroaders use these
by the bushel, at various voltages, usually lower than 9V, but mebbe also
9-12V. Connect a few in series for your voltage, and you'll have a more
uniform lighting.
----------------------------
Mr. P.V.'d
formerly Droll Troll
Maybe a 5-cell MagLite bulb; may need a diode in series. If it's running on
AC a pair of diodes in parallel with one pointing in each direction. This
would be rather bright and might draw too much current.
He has only 9 volt source. Zener will subtract 3.3 from that so he can use
6 volt lamp. That is assuming the his source is DC.
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things)
Just put a 'regular' 12v Grain of Wheat one in, it'll be a bit dimmer but it
will never burn out ! Well, almost never.......
If you're ambitious, you could use a few of those nice white LEDs now on the
market and they won't butn out either....
jay
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