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Philco 90 - Extra Paper Caps?
#5

Thanks for the info guys. I just wanted to be sure that there was not some product design change causing these caps to be added for performance reasons. I am comfortable now that they are not. After having rebuilt the bakelite blocks and the metal filter blocks, the radio plays very well.

On a side note, I still need to rewind the primary of the RF transformer, which is open. The radio plays beautifully with the open primary bridged by a 20K resistor. In fact, I am wondering if there is anything to be gained by rewinding the primary of this transformer? I see that the later Philco 70's use an open primary with the B+ feed to the RF tube plate (shunt fed) via what appears to be an RF choke.

Ed


Messages In This Thread
Philco 90 - Extra Paper Caps? - by etech - 04-06-2008, 10:54 PM
[No subject] - by planigan - 04-07-2008, 01:16 AM
[No subject] - by BDM - 04-07-2008, 01:53 AM
[No subject] - by Ron Ramirez - 04-07-2008, 08:15 PM
[No subject] - by etech - 04-07-2008, 08:40 PM
[No subject] - by etech - 04-08-2008, 08:45 PM



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