Watson A.Name - \"Watt Su
Guest
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Posted:
Sat Mar 12, 2005 6:10 am Post subject:
Re: #47 LED lamp? |
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"Neil Preston" <npreston@nospamgeocities.com> wrote in message
news:X5tYd.5112$yp.2790@newssvr11.news.prodigy.com...
| Quote: | Has anyone ever come out with an LED drop-in replacement for the #47
(and
similar) lamp bulbs?
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Well, that depends. The #47 lamp was commonly used in All American 5
tube radios as a part of the filament string. If you use LEDs there,
you must maintain the total current thru the lamp with an equivalent
resistance in parallel, and also rectify the AC. If this is your
intent, then you might consult the denizens on rec.antiques.radio+phono
newsgroup. If not, then just put a diode and resistor in series with
the LED(s) to limit current and rectify AC. I have been able to squeeze
three LEDs in the base of a lamp with a little filing of the LED.
So it depsnds greatly on where you're going to use the substitute. If
it's in certain locations, the LEDs may be put out light that's too
directional. And of course, the color may be a problem. So you see,
there are many factors, electrical *and* physical, to determine before
you might come up with a suitable LED substitute.
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