On Sat, 09 Jun 2007 01:42:31 GMT, Rich Grise wrote:

Posting from my other news client, and forgot to switch nyms.

Thanks!
Rich

On Sat, 09 Jun 2007 01:40:10 +0000, The Newsgroup Wacko wrote:

Yes, I have successfully flashed an LED by 1/2 556. The "on" times and
"off" times are independently adjustable, and all of the values are pretty
much as per usual. With a 4.7 tantalum, I can get the flash rate down to
about 1.7 Hz (according to the counter that came with the scope), and,
much to my amazement, with no capacitor AT ALL, it gave a pretty
reasonable approximation of a square wave (admittedly, with a little
glitch on the rising edge) at like over 200 KHz! If I had the motivation,
I'd bother to calculate the capacitance of my ProtoBord, but arithmetic
isn't my favorite thing to do. One thing that I was glad to see happen is
that with the 100K pot in series with the 1K fixed, I actually get a 200:1
range, both for "on" time" and for "off" time, so I guess that means I can
tune the duty cycle from 1% to 99%, and in between them, I can dick around
with the frequency. :-)

Cheers!
Rich


Jeez, what a dope. Not for the post account error... for the post
itself.

How many YEARS did it take you to be able to construct a variable
modulation pulser?