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Capacitance Decade Switch for Guitar

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KungFuJosh:
Hi,

I have a question I'm hoping I can get some help with. There's a decade switch (capacitance only) that Les Paul used on some of his guitars. It's an 11 position switch, but only used 4 capacitors (10 capacitance values and 1 bypass position). Here's how they show it in the diagram:


I can't find a detailed diagram or any more info on the actual switch. I assume it's playing games rotating things in and out of parallel or series to get the appropriate values. Based on the spread of the resistors, I assume it would go something like: 47nF, 56nF, 68nF, 82nF, 100nF, 120nF, 150nF, 180nF, 220nF, 270nF. The numbers wouldn't likely be exact, but I imagine close enough. Or maybe it had some other funky combination of capacitance values (I will eventually be able to measure the values on a different guitar).

Any ideas of what switch would be used and how it was wired to accomplish this?

Worst case, I can get an 11 position switch and just load it with those values, but it would be cooler to make it more like the original.

Thanks,
Josh

csaaa:
Online measurement may be affected by interference from other components, especially capacitors, and may not yield accurate results

themadhippy:
The 10 positions with 4 caps  sounds like could be  a bcd switch,more than likley custom made to get the added bypass

ledtester:
The cap values are basically in a geometric series with common ratio 2 so the decade switch looks like a "binary thumbwheel switch":

https://www.mouser.com/c/electromechanical/switches/thumbwheel-switches-pushwheel-switches/?output%20code=Binary

Here is a project to create a low-cost multi-decade capacitor substitution box out of several of these kinds of switches:

https://www.eevblog.com/forum/projects/low-cost-programmable-decade-capacitor-for-prototyping-convenience/

themadhippy:

--- Quote ---so the decade switch looks like a "binary thumbwheel switch":
--- End quote ---
There also available in standard rotary switch style,for example
https://int.rsdelivers.com/product/lorlin/bcks1001rs/lorlin-16-position-bcd-rotary-switch-150-ma-250-v/7392915
yea it says 16 way,but shifting the end stop soon makes it 10

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