Reply-To: "Steve Barker"
From: "Steve Barker"
Subject: Re: Another 12V project Help needed
Organization: Yeah, Ok.....
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Date: Tue, 17 Dec 2002 02:58:52 GMT
NNTP-Posting-Date: Mon, 16 Dec 2002 20:58:52 CST
Ok, I've got this thing built on the test board and working fine. One more
question and I'll leave you alone. I need it to be able to have the power
supply and the trigger be separate inputs. I need it to be in such a way
that I could trigger it for say one second (or even momentarily) and still
get 5 seconds output. And it would have to reset each time the trigger goes
away. I hope I'm somewhat clear on this, I'm no electronics wizard.
UP (Mopac) Coffeyville Sub MP 308
Nikon CP 995 PSP 7.04
Remove the "nospam" from my address to abuse my email box.
"Terry Pinnell" wrote in message
> You didn't clarify why you said the trigger could be applied for 'up
> to a minute'?
> That aside, you just need the same circuit I drew for you in reply to
> your post on 13th Dec, i.e the one at
> except that you should raise the value of Ct to say 22 uF and change
> Rt to a pot of 470k (plus a series resistor of say 1k to establish a
> very brief minimum period). Or use any other convenient values as
> already explained in the notes with that schematic.
> If you also need details of how to connect it to your relay, refer to
> I've never used a snow plow, but I'm curious why you wouldn't instead
> want the greater manual control of a simple toggle switch with UP and
> DOWN positions? Or is it a matter of wanting to use your hands for
> plow control for the absolute minimum time, so as to concentrate on
> steering? If so, maybe a foot-switch or button could be an
> Also, I've assumed a nice clean 12 V supply. At the very least add a
> 47 uF cap across the supply, close to the 555 pins. And if that proves
> inadequate, add the fuller noise suppression precautions recommended
> by Fred Bloggs in the previous thread.
> Terry Pinnell
> Hobbyist, West Sussex, UK