ROG Grace/Big Daddy Potentiometer Question

[Pakaloabob]

The schematic for Grace/Big Daddy distortions on the Runoffgroove website http://runoffgroove.com/grace.html has a "Drive" potentiometer with N.C. written at contact #1. I am not sure what this means. If it were to be connected as a variable resistor I thought that contacts #2 and #3 would be attached together.
Can anyone clue me in?

[head_spaz]

N.C. typically means No Connection.
In this circuit the potentiometer is wired, and used as a Variable Resistor, rather than it's traditional role of Voltage Divider.
Wired as a variable resistor, it works the same if you connect that loose end to the wiper, OR leave it floating.
I usually connect the loose end to the wiper as you suggest, rather than have it floating and acting like an antenna.
Good luck with your project.

[B Tremblay]

When wiring a pot as a variable resistor, shorting lugs 2 and 1 will result in lower overall resistance as the pot is turned up (clockwise).  If you short lugs 3 and 2, the pot will increase in resistance when rotated CW.

In the case of the Grace/Big Daddy, the 1k pot parallels the 386's internal 1k35 gain-setting resistor.  When the pot is at minimum, the overall resistance is about 570 ohms.  As the pot is turned up, the resistance decreases and the gain increases.

[Pakaloabob]

Thanks for clearing that up. I guess I was so used to seeing pots wired as variable resistors with 2/3 connected, it freaked out when I saw something different