circuit help

[Karl W4KRL]

Sandy,

Good call! See revised schematic.

73 Karl

-----Original Message-----
From: Nan and Sandy Sanders [mailto:radiodog77 at pobox.com] 
Sent: Tuesday, July 8, 2014 7:31 PM
To: W4KRL at arrl.net; 'Mike O'Dell'; tacos at amrad.org
Subject: RE: circuit help

Put a diode in the led common line so you cannot back bias the leds. 
Might be worth it to do some testing and see how hard it is to blow the leds
in a switch.
      Sandy
      WB5MMB


At 03:49 PM 7/8/2014, Karl W4KRL wrote:
>Mike,
>
>A probable flaw in my scheme, Rob's, and yours is that the OFF LEDs will be
>back biased by up to 24V due to a reverse path through each load impedance.
>Most LEDs won't tolerate that. Off hand, I do not see any way to overcome
>this defect in any scheme.
>
>Karl

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