[sdiy] Dumb PWM question

[Tim Daugard]

From: "jbv" <jbv.silences at club-internet.fr>

> than a sine) to show what I have in mind : on the 1st part (top) the period
> ratio
> is 50%, and it varies in the 2 other parts :
> http://jbv.silences.club.fr/sdiy/PMW_example.jpg

. . . and cleaner to see the problem. With only one cycle of the waveform, your ouput is
changing in anticipation of a change in the input. This is a time machine (unless the
output is based on the input of a previous cycle.) With one cycle of waveform, your
waveform violates the laws of physics (as I understand them).

> I don't know if your circuit allows that...

Now stretching the input, and then speeding up to recover the stretched time might be
possible - a lag circuit followed by a zero crossing switch to a circuit that will speed
up the charge on a cap until the signal catches up. Hmmm interesting, another circuit
design to go into a sketch book for later.

Tim Daugard
AG4GZ 30.4078N 86.6227W Alt: 12 feet above MSL
http://home.sprintmail.com/~daugard/synth.htm
http://home.earthlink.net/~synthfred/h_toctop.htm (Fred's online edition)