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37-38 Purpose of Resistor 40
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http://www.nostalgiaair.org/PagesByModel...013204.pdf
Anyone know the purpose of resistor 40 in the Philco 37-38? It appears to simply place a 10ma load on the C-9 battery! I see no other purpose. When the switch is ON, C+ is connected to the chassis ground, and C-9 is connected through the switch to resistor 40 (unless I am missing something!)

Was this to help sell Philco batteries? It certainly complicates powering this set from the usual ABC battery eliminator! When I restored my set, I had to build a separate C supply for C-9, and used my AES K-101A to provide the C-3 and the rest of the voltages.

Thanks!


Messages In This Thread
37-38 Purpose of Resistor 40 - by davemc - 08-24-2012, 12:38 PM
RE: 37-38 Purpose of Resistor 40 - by davemc - 08-25-2012, 05:52 PM



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