06-10-2011, 09:04 AM
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.
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
