Tone Wheel Recap - Voltage Choice of Capacitors ?

[tpappano]

No argument from me on that! The filters are ‘series resonant', if you replaced the cap with a dead short you would still have a tone. Reduce the cap to zero uf, you'll have nothing 8)

[David Anderson]

That's what I find cool about the series resonant circuit. Usually, when you put additional passive components in series a circuit, you lose some signal, but when an LC series resonant circuit is properly tuned, the output increases over the inductor alone. The AC impedances cancel out, and the only signal losses are the resistive losses in the inductor and capacitor.

[Randall_Dibble]

Ok, I've been thinking this out and is it correct assume that if I had hot note, to strong of signal, that instead of screwing with the tone adjustment, pun intended, I could place in parallel a very low value cap 0.005uf or so to tame it.

Is there a way to do similar thing to bring up the signal strength ?

Don't want really screw around with calibration anymore then I have too.

As a Musician the Voicing of the tone generator is of great importance.

[David Anderson]

Yes, you can add capacitance to detune the filter and reduce output.

There is an optimal capacitance value that will maximize the output of a single tone's frequency. It might be 95nF, 98nF, 100nF, 102nF, 105nF, 110nF, etc... Any capacitor value higher OR lower will reduce output. Think of it as tuning a radio with a signal strength meter to a particular station; it's essentially the same thing. At one point as you turn the dial, you will reach maximum signal reception. It's not going to get any higher than that. You are tuning a filter to let one frequency through and block others.

To put it another way, it's the combination of the filter's inductance and the capacitance that tunes the filter. That's what a lot of people don't understand. Hammond first installed the inductors on the filter tray and then selected capacitors in the manufacturing process at a station to tune the filters. Then the final calibration was done.

[RogerRabbit]

This is why I recapped my C3 the lazy way and swapped the entire filter tray from from my scrapped TTR-100 TWG, added the uncapped coils and it was done. Just had to adjust three pickups to be right on the curve.