Mini Metronome

Posted in Metronome, on 2015-07-13

Circuit diagram:

Mini Metronome

Parts:

  • P1______100K Linear Potentiometer
  • R1_______10K 1/2W Trimmer Cermet
  • R2_______10K 1/4W Resistor
  • R3______330K 1/4W Resistor
  • R4_______50K 1/2W Trimmer Cermet
  • R5______100K 1/4W Resistor
  • R6,R7_____1K 1/4W Resistor
  • C1________1µF 63V Polyester Capacitor
  • C2_______10nF 63V Polyester Capacitor
  • C3_______47µF 25V Electrolytic Capacitor
  • IC1_____NE555 General purpose timer IC
  • Q1,Q2___BC560C 45V 100mA Low noise High gain PNP Transistors
  • Q3_____ZTX753 100V 2A PNP Transistor
  • SW1______SPST Switch (Ganged with P1)
  • SPK______8 Ohm 40mm. Loudspeaker
  • B1_____12V Battery (MN21, GP23A or VR22 type)

Notes:

  • Q1 & Q2 provide linear frequency operation of IC1 following P1 resistance variation.
  • Q3 was added in order to obtain a louder click, similar to clockwork metronomes.
  • A 12V micro battery was used to obtain a higher output power and more compactness.
  • Rotate P1 fully towards R2, then set R1 to obtain 40 beats per minute (compare with another metronome).
  • Rotate P1 fully towards R3, then set R4 to obtain 208 beats per minute.
  • Finally mark the entire scale with the usual metronome steps, as follows: 
  • 40 - 42 - 44 - 46 - 48 - 50 - 52 - 54 - 58 - 60 - 63 - 66 - 69 - 72 - 76 - 80 - 84 - 88 - 92 - 96 - 100 - 104 - 108 - 112 - 116 - 120 - 126 - 132 - 138 - 144 - 152 - 160 - 168 - 176 - 184 - 192 - 200 - 208.

If you like this page, please consider sharing

Credits

Source