SHADOW METER TO LED CONVERSION

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SHADOW METER TO LED CONVERSION

AI2V
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Posts: 201
Threads: 26
Joined: Dec 2005
City: Morris Plains, NJ

06-13-2011, 02:34 PM

Some have asked for a quick explanation of how this circuit works: the zener sets a fixed voltage (e1) below the B+. As the receiver is tuned to a station, the voltage at the load end of the 8K (e2) rises and approaches the full B+. This difference between these two voltages (e2-e1) lights the LED.

If an LED were simply placed across the 8K, the LED would become dark when tuned to a station, just the opposite of what's desired.

Pete AI2V

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SHADOW METER TO LED CONVERSION - by AI2V - 06-10-2011, 10:04 AM

Re: SHADOW METER TO LED CONVERSION - by TA Forbes - 06-10-2011, 11:04 PM

Re: SHADOW METER TO LED CONVERSION - by AI2V - 06-11-2011, 09:14 AM

Re: SHADOW METER TO LED CONVERSION - by TA Forbes - 06-11-2011, 08:19 PM

Re: SHADOW METER TO LED CONVERSION - by AI2V - 06-13-2011, 02:34 PM

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