qbone
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Help - Very low frequency oscillator / timer (<1Hz)
Hey guys.
I need to make oscillator / timer that toggles a relay every 5 sec, so that would make it 0,2Hz
I feel I have searched high and low for a solution, but I just can't get any of them to work properly, either they dont oscillate/toggle or they are oscillating too fast - like never under 1Hz.
I have tried the design with an astable made from a 555, but I got really inconsistent timings from that, it was like 6 sec HI, 3 sec LO, 8 sec HI, 9 sec LO, 3 sec HI, 5 sec LO - Just really random it seemed.
Then I moved on to try making the circuit with an astable multivibrator made from two BC547, but that either stalled or oscillated way to fast, same did the relaxation oscillator made from 74HC04 and 74HC132.
Maybe it all comes down to me choosing the wrong values, but if someone could help me out, it would be very much appreciated!
- - - Updated - - -
Oh yeah, because it need to toggle a relay every 5 sec, I need a 50% Duty cycle
Hey guys.
I need to make oscillator / timer that toggles a relay every 5 sec, so that would make it 0,2Hz
I feel I have searched high and low for a solution, but I just can't get any of them to work properly, either they dont oscillate/toggle or they are oscillating too fast - like never under 1Hz.
I have tried the design with an astable made from a 555, but I got really inconsistent timings from that, it was like 6 sec HI, 3 sec LO, 8 sec HI, 9 sec LO, 3 sec HI, 5 sec LO - Just really random it seemed.
Then I moved on to try making the circuit with an astable multivibrator made from two BC547, but that either stalled or oscillated way to fast, same did the relaxation oscillator made from 74HC04 and 74HC132.
Maybe it all comes down to me choosing the wrong values, but if someone could help me out, it would be very much appreciated!
- - - Updated - - -
Oh yeah, because it need to toggle a relay every 5 sec, I need a 50% Duty cycle