No, not a variable resistor, but variable capacitor. Do a google search on "Crystal Set", or go to http://theradioboard.com/rb/index.php http://theradioboard.

No, not a variable resistor, but variable capacitor. Do a google search on "Crystal Set", or go to http://theradioboard.com/rb/index.php http://theradioboard.com/rb/index.php