10 Turn Pot Forms Frequency Readout - Letís say you are designing a signal generator for a test fixture. To adjust the frequency you
would like to use a ten turn pot with a nice dial mechanism attached as a frequency display. However, a display range of 0 to
9.99 would be impractical since . . . [Hobby Circuit designed by Dave Johnson P.E., 01/27/08]
Control Variable LED Intensity - The circuit below uses power from four rechargeable AA NiMH cells to drive 3 white LEDs. A
potentiometer varies the duty cycle of a pulse width modulator circuit to vary the intensity of the LEDs from 0% to 100%.
The beauty of the circuit is that when the . . . [Hobby Circuit designed by David A. Johnson P.E., 09/27/09]