Search found 23 matches

by frank_fg
Sat Jun 28, 2008 7:23 am
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Al On another project working with a servo, I turn the pot until it was were I wanted it, measured the resistance, and did the same thing on the other side. It worked, but it got there fast. I don't want this to happen her. Spec's are: Oscilliation frequency 50 Hz and 250 Hz, At 0.8 ms to 2.5 ms...
by frank_fg
Fri Jun 27, 2008 4:29 pm
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi!


Looks like it worked.

The valuase are:

R5 = 33k
R6 = 100k
R7220k

C6 = 0.022 ufd

It seems more stable at 250 Hz,
Jitters at 50HZ

thanks

Frank G.
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by frank_fg
Fri Jun 27, 2008 4:24 pm
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Al

Hope you thi9s works.



Image

Image
by frank_fg
Fri Jun 27, 2008 12:15 pm
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Al Good news! Fixed my problems a and b, the a problem was me, the brain was not engaged, as I was drinking my coffee this morning it accurred to me that the servo was turning counter clockwise only, which tells me that the one-shot had to been working, and the negative triggr was so small and p...
by frank_fg
Thu Jun 26, 2008 11:08 am
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Al How did you get the photos on the forum? Do you get the magazine Servo? If you do, it is on May issue on page 34, called Servo buddy. I'm sorry I did not say it before, but I did not want to give it away. But I see, that I'v taken so much of your time, and I do appriciate. IC2 555 timer is th...
by frank_fg
Wed Jun 25, 2008 4:04 pm
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Al You got it, the only thing is the diode come first, but that works. Well Al I have worked on some real neat circuits in the past, but that the problem in the past. What I did was to make my own differenntiator network and substituted it, and woulden you now it! it worked the same. I'm at a lo...
by frank_fg
Wed Jun 25, 2008 9:28 am
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

Hi! Sorry to say that the diode is not in backwards. All the parts are in correctly, however there is that human factor. what is throwing me off, is the fact that when I remove one end of the resistor R4 I can see the capacitor and diode in action. Tha capacitor is charge to 5v, then the diode is fo...
by frank_fg
Tue Jun 24, 2008 8:06 pm
Forum: General Discussion
Topic: 555 Timer triggered fropm a differentiator.
Replies: 31
Views: 11966

555 Timer triggered fropm a differentiator.

:???: Need your help, it been some time that I troubleshot a circuit. Hi! I just bought a kit that has two 555 timers that run a servo. IC2 is 50 Hz oscillator and IC3 is a one-shot. IC2 pin 3 from the oscillator feeds C4 .001 ufd cap which is connected to D3 1N914 diod and R4 10k resistor, which fr...