After reading lots of differing & conflicting explanations of how the Fender TBX tone control works, I decided to take apart my Strat & find out. This is a '94 Strat Plus with Lace sensors. I don't know if there are variations of the TBX. I desoldered the resistor & cap so that I could get accuarate measurements. So, here's the deal. It looks like a double stack pot with 1 shaft (not dual concentric), but the pots are NOT standard pots by any definition. There is a detent position at the center of the pots' rotation. Fender only uses pins 2 & 3 of the pots (the wiper & the terminal on the clockwise end of the pot). I think it's best to think of these pots as 3 separate functions - 0-5 on the knob, the detent postion in the middle, and 5-10 on the knob. Measuring between pins 2 & 3, the bottom pot (with the shaft up) is a standard 250K audio taper pot from 0-5 on the knob (CCW end to just before the detent position). At the detent position, it goes open (like a no load tone pot). From 5-10 on the knob (the detent position to the CW end), it remains open & out of the circuit. Measuring between pins 2 & 3, the top pot (with the shaft up) is a 0 ohm connection from 0-5 on the knob (basically a solid wire connecting the pins). At the detent, it remains 0 ohms. After the detent from 5-10 on the knob, it is a 1M ohm linear pot. I've made 3 schematics of the 3 phases of the tone control. 0-5 on the knob before the detent, it looks like a standard Fender tone control circuit with an 82k resistor added to ground: At the detent position, the standard tone control is removed from the circuit due to the bottom pot going open at the detent, but the 82K resistor to ground (in parallel with the pickup(s)) stays: 5-10 on the knob after the detent, the 1M linear pot comes into the circuit in series with that 82k resistor. As you turn the knob, the added resistance reduces the effect of that resistor's load on the pickup(s) until at 1M, it has almost no effect. I found that removinging the TBX control (with a switch) did provide a little more brightness than even the full CW setting of the TBX, though. I find that I usually like the TBX set at just beyond the detent (6 on the knob), so I might try increasing that 82K resistor a little.