Jog timer

Circuit diagram:

Component:

R1_____________47K 1/4W resistor

R2_____________10M 1/4W resistor

R3______________1M 1/4W resistor

R4_____________12K 1/4W resistor (see note)

C1, C3__________10µF 25V electrolytic capacitors

C2____________100nF 63V Polyester Capacitor

D1___________1N4148 75V 150mA diode

IC1____________4093 Quad 2-input Schmitt NAND gate integrated circuit

IC2____________4060 14-stage ripple counter and oscillator integrated circuit

IC3____________4017 Decimal Counter with 10 Decoder Outputs

Q1____________BC337 45V 800mA NPN transistor

SW1___________1-pole 9-position rotary switch (see note)

SW2___________Single-pole single-throw slide switch

BZ1___________ Piezoelectric Generator (with built-in 3KHz oscillator)

B1____________3V battery (two 1.5V AA or AAA batteries connected in series, etc.)

Equipment application:

This circuit was developed because some visitors to this website requested a timer that would emit a beeping sound after 1 minute, 2 minutes, 3 minutes, etc., for jogging purposes.

As shown in the circuit diagram, SW1 is a 1-pole 9-position rotary switch. When the switch is set to position 1, the piezoelectric buzzer emits three short beeps per minute. In position 2, the same thing happens after a 2-minute delay, and so on, reaching a maximum interval of 9 minutes in position 9.

Note:

- If only one time setting is needed, the rotary switch can be replaced with a hardwired connection.

- DIP switches can be used instead of rotary switches. Please note that only one switch should be used at a time, otherwise the device may be damaged.

- By changing R4 from 10K to 15K, you can get more or less than three short beeps after the preset time delay.

- To get a one-second beep only after a preset time delay, disconnect pin 9 of IC1C from pin 9 of IC2 and connect it to pin 8 of IC1C.