RE: Terry's DRSSTC - Frequency/Pulse Width Controller

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Steve Conner" <steve.conner@xxxxxxxxxxx>

>However, most LMC555 circuits and their types are  "F : 1/R"  type circuits
>so the frequency control is not at all linear....
>I just wanted to check to see if anyone and an easy simple way to do
>that?

I designed an analog circuit that does it using a voltage controlled current
source-
http://www.scopeboy.com/tesla/ol2tg.html

By putting a pot in series with R7 you can have the adjustable on-time you
want. The on-time will interact slightly with the break rate. If you are
bothered by this you need to leave R7 fixed and trigger a second 555 off
this circuit to produce the variable length pulse.

I also wrote a DDS synthesizer routine for the PIC that generates pulse
trains between 1 and 1024 per second but I never figured out how to
implement an adjustable on-time. I prefer the analog circuit anyway as it's
less likely to crash O__o


Steve C.