RS-232 Tx / Rx monitoring LEDs?
cclist at sydex.com
Fri Aug 21 10:57:30 CDT 2015
On 08/21/2015 08:36 AM, dwight wrote:
> I was going to add something but it has already been said several
> times. I will add that if using a LED on an AC like signal of high
> voltage, one should use a diode. I recommend using a shunt diode
> rather than a series diode when high voltages are being dropped by
> the resistor. It reduces the need for a high voltage diode but makes
> the resistor hotter. Some red LEDs glow orange when not protected
> from 12VAC. You can ask how I know. Dwight
Ever take a close look at a string of Christmas-tree LEDs? Most are
composed of a string of LEDs hooked directly across the AC line--no
rectifier diode to be found.
Some seek to reduce the 60Hz flicker by employing two strings to
illuminate on both half-cycles, reducing the flicker somewhat. Since
my eyes react to the flicker (it's like ants crawling over the string),
I found that simply employing a full-wave bridge rectifier can reduce
the appearance of flicker tremendously.
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