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Philco #91B Shadow Tuning Question
jjfritz5528
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City: Lancaster State, Province, Country: PA
#2

02-10-2024, 04:25 PM
Well, I did some testing, using a resistor decade box. Started with a 1k ohm resistor in series with the Shadow meter (as shown on the schematic) and reduced down to 15 ohms in steps. I got the same voltage across the meter, regardless of the resistor.  It was approx 4.5V to 6.0V.
SO I removed the resistor completely. I do get a good variation in the shadow width while tuning a station. Made some very minor positioning adjustments to the lamp.
Thanks
John N3MUN
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RE: Philco #91B Shadow Tuning Question - by jjfritz5528 - 02-10-2024, 04:25 PM



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  1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration