5 ms·
Depending on the supply requirements, he might use voltage ripple as a reference. With an unsmoothed rectified supply you get a nice "pulsed" input anyway: ht
by jonathonf 12y ago
Depending on the supply requirements, he might use voltage ripple as a reference.
With an unsmoothed rectified supply you get a nice "pulsed" input anyway:
http://falstad.com/circuit/#%24+1+5.0E-6+1.8479586061009856+53+5.0+50%0Av+128+272+128+64+0+1+50.0+5.0+0.0+0.0+0.5%0Ad+224+128+288+64+1+0.805904783%0Ad+224+128+288+192+1+0.805904783%0Ad+288+192+352+128+1+0.805904783%0Ad+288+64+352+128+1+0.805904783%0Aw+128+64+288+64+0%0Aw+288+192+288+272+0%0Aw+288+272+128+272+0%0Aw+224+128+224+368+0%0Aw+224+368+464+368+0%0Aw+352+128+464+128+0%0Ag+224+368+224+400+0%0Ar+464+128+464+368+0+100.0%0AO+464+128+528+128+0%0Ao+13+64+0+34+5.0+9.765625E-5+0+-1%0A http://falstad.com/circuit/#%24+1+5.0E-6+1.8479586061009856+...
- smoyer 12y agoTrue but you'd expect that to be 120Hz rather than 60Hz.
- jonathonf 12y agoSo you could: a) use a half-rectified supply b) halve the count. A) would be easier. :)
- smoyer 12y agoTrue ... not so good for efficiency and you'd need a bigger smoothing capacitor. (I'm assuming since this is all discrete, there's no need for a fully regulated power supply).
- morcheeba 12y agoYou'd want a fully regulated power supply for this, /especially/ because it's discrete. You want the LEDs to remain constant brightness, but, more importantly, you don't want an unregulated power supply to overvolt and destroy all this hard work.
- dogma1138 12y agoUse a diode so you only get half of the sin waves, that's 60hz which makes it very easy to build a clock off since you don't need to do any multiplications on the base clock frequency it self.
- deleted 12y ago[deleted]