Fixed frequency Variable duty cycle with 555 - del00012
This
circuit is based on a very old application note from exar, in this the
frequency
is fixed by IC1 and IC2 -P1 controls the duty cycle. you need to
compute
the R and C values to get what you need, LM555 data sheet.
You have to study the circuit and do something more
innovative perhaps, just
copying is ok for learning but it will get you nowhere, so learn and
then
innovate, the eagle circuit is given below so you can learn by editing
it,
also design a PCB with it, and you can even make a PCB at home to
learn,
but it is always good to get PCBs done by a PCB vendor, but you should
understand
his problems, then you will design well, so make a few PCBs.

See Larger Circuit. 555 Variable Duty Cycle
Oscillator
Edit the circuit eagle cad file del00012.zip, eagle cad has a free version for
windows and linux.
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