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SHADOW METER TO LED CONVERSION
#1

In case anyone missed it in an earlier post, here's the schematic of the shadow meter to LED conversion mod. Please comment on success or failure but NOT if you used a 10mm LED or one brighter than 4K mcd- there is usually not enough current to drive those. Also, don't get fancy and expect much light through both a band mask and a dial together. None of the values are critical, not even the zener diode. The 8.2 volt zener works fine but so do other zeners within a volt or two.

This circuit has worked well in several manufactures' superhet radios, not just Philco's. If you attempt non-Philco's, you must separate out the B+ lines to the tuned RF amp and IF tubes only, not any oscillator, detector, mixer, or audio tubes. This circuit will not work in a radio with only a two section tuning cap.

Pete AI2V


Messages In This Thread
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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