flashing led based on IC NE555

Double flashing led based on IC NE555
This circuit is used to flash alternately high brightness LED 4
When the cursor turns trimmer R1, can be programmed from 22 to 48 flashes per minute (these numbers depend on the tolerance of the electrolytic C2, tolerance up to
40% with an electrolyte!). If we want to reduce the number of flashes per minute, increase the capacity of C2 by passing 10 to 22 uF. The formula to calculate the number of flashes per minute is:

Number of flashes / min = (86 400 C2) (R1 + R2)

R is in k and C in uF, 86 400 is the number obtained by multiplying the constant 1440 provided by the manufacturer of the integrated circuit by 60 seconds to one minute.
We plan to C2 10 uF, but if we go up a 22 uF how lightning will we?
Suppose that R1 is set to its maximum value of 220 k, we have:


N = (86400: 22): (200 + 100) = 13 flashes / min.

For more flashes / min you have to turn the trimmer R1 to 3 / 4 of its stroke (about 50 k) and we will have:

N = (86400: 22): (50 + 100) = 26 flashes / min.

One can also vary the number of flashes / min by changing the value of R2.
the device can be powered by a 9 V battery or a car battery or 12 V by a power supply 12 V.

scheme has led flasher:

scheme led to:

Component List
R1 ...... 200 kOhms trimmer
R2 ...... 100 kOhms
R3 ...... 330 Ω
R4 ...... 330 Ω
C1 ...... 47 uF electrolytic
C2 ...... 10 uF electrolytic
C3 ...... 10 nF polyester
DL1 ..... High Brightness LED
DL2 ..... High Brightness LED
DL3 ..... High Brightness LED
DL4 ..... High Brightness LED
IC1 ..... NE555
S1 ...... toggle switch
PP ...... jack 9 V battery