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Sounds like great news! I'm sure it's lots of work flopping back and forth between two schematics, but nothing ventured, . . .
The 45K, 5 watt resistor seemed odd and purposeless as drawn in your schematic. Seems it should have been in series with those other two. Is that part of what was changed?
(This post was last modified: 08-30-2019, 10:52 PM by
Jake Blake.)
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It is now wired exactly like the Jackson-Bell Model 4 with all new parts except for the tube sockets, power transformer, the coils, the speaker assembly, and 2 gang variable condenser. I did add a .068 condenser across the 400 ohm resistor in the power supply to decouple some variation off the grid bias, although the difference is minimal with or without it. If you give it a while to warm up, at least 5 minutes, it picks up a number of stations now. The volume on many of them is not very high, but they are listenable. I think it's about the best I can hope for. I wonder if this was one of those ultra cheap sets radio dealers of the time, the Great Depression, had in their store so they could advertise them at a low price, then up-sell customers by showing them how much better their other, slightly more expensive sets performed. I remember reading something about this in the magazines in the links John (Eliot Ness) posted earlier in this thread. Very interesting reading there. I downloaded it all.
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Jake, the 45k is part of a voltage divider formed by it and the 20k 5w.
Steve
M R Radios C M Tubes
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Yes, I recall numerous remarks made about the those low-price leaders also.
Glad you got it playing bud. What's next on the agenda?
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"Jake, the 45k is part of a voltage divider formed by it and the 20k 5w."
Thanks.
If I'm understanding correctly, they create a current draw with more than one, stable voltage at different points along it?
(This post was last modified: 08-31-2019, 09:10 AM by
Jake Blake.
Edit Reason: object tense
)
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Yes, jake. They are used in a similar way to the candohm resistors in the Philco sets, which are tapped at various resistances to provide bias voltages to various grids in the circuit. It's the same principle, multiple resistances acting as a voltage divider.
