650B tone control values - Printable Version

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+--- Thread: 650B tone control values (/showthread.php?tid=1151)

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650B tone control values - BDM - 05-25-2008

Guys, I want to replace the caps inside my tone control. The part number from the schematic is a #30-4343. I don't see this one listed on Chucks site. I assume points 1 2 3 & 4 are as follows. 1 = open, point 2 is the first position back to the cap and so on for points 3 & 4? Thanks.

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- BDM - 05-25-2008

I found it listed in the schematic as .01 .003 and .01 in that order. All listed under part #57. Am I correct?
http://www.nostalgiaair.org/PagesByModel/824/M0013824.pdf

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- Ron Ramirez - 05-25-2008

Yes, those are the correct values.

Point 1 - none of the caps are in the circuit.
Point 2 - shorts out the first .01 uF cap, reducing or eliminating bass.
Point 3 - brings the .003 uF into the circuit, leaving the first .01 shorted and adding just enough bass to make the sound mellow without reducing treble by any appreciable amount.
Point 4 - puts the second .01 in parallel with the .003, leaving the first .01 shorted; produces lots of bass, cuts treble significantly.

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- BDM - 05-25-2008

Thanks Ron

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- BDM - 05-25-2008

Fixed! Much better!!

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