•  
  •  

Alternating Flasher

- Designed by Naveen P N

This circuit uses three easily available 555 timer ICs. All three work as astable multivibrators. The first 555 has an on period and off period equal to 1 sec. This IC controls the on/ off periods of the other 2 555s which are used to flash two bulbs through the relay contacts.
The flashing occurs at a rate of 4 flashes per second.
The diodes are used to protect the 555 ICs from peaks. The relays should have an impedance greater than 50ohms i.e, they should not draw a current more than 200mA.
The flashing sequence is as follows:
The bulb(s) connected to the first relay flashes for about 1 sec at a rate of 4 flashes per second. Then the bulb(s) connected to the second relay flashes for 1 sec at a rate of 4 flashes per second. Then the cycle repeats.
The flashing rates can be varied by changing the capacitors C3 and C5. A higher value gives a lower flashing rate.
Note that the values of C3 and C5 should be equal and should be less than that of C1.
The value of C1 controls the change-over rate ( default 1sec). A higher value gives a lower change-over rate.
If you use the normally open contacts of the relay, on bulb will be OFF while other is flashing,and vice versa.
If normally closed contacts are used, one bulb will be ON while the other is flashing.

If there are any problems please contact webmaster@electronic-circuits-diagrams.com

Please share & like

DC 4.5-30V 0-50A Dual LED Digital Volt meter Ammeter Voltage AMP Power Meter 12V
$9.66 DC 4.5-30V 0-50A Dual LED Digital Volt meter Ammeter Voltage AMP Power Meter 12V picture
Ampere Gauge / Ammeter fits JD Tractors (20-0-20 Ammeter) Black Face (2 pcs per
$18.99 Ampere Gauge / Ammeter fits JD Tractors (20-0-20 Ammeter) Black Face (2 pcs per picture
UNI-T UT56 Portable Digital Multimeter AC/DC Ammeter Voltmeter Frequency
$66.86 UNI-T UT56 Portable Digital Multimeter AC/DC Ammeter Voltmeter Frequency picture
Amprobe AC Volt Ammeter Chart Recorder Untested
$40.0 Amprobe AC Volt Ammeter Chart Recorder Untested picture
USB Tester Voltage Meters Detector Digital Voltmeter DC Current Meter Ammeter
$9.99 USB Tester Voltage Meters Detector Digital Voltmeter DC Current Meter Ammeter picture