Re: Simple LED Alarm Bell for CCTV recorder

[Crash Gordon® <NONE@xxxxxxxx>]

I need some really small one's without shoulders (maybe 1/8" dia. or =
less...preferably 12v to keep it simple. I'm prototyping an idear for =
alarm system. They got anything in Newark cat.? I also need about 10 =
feet of fiberoptic...any scrap junk is fine it's not for =
communications...if anyone's got a piece? I don't want to buy a whole =
roll in case my project is a bad idea.

"Jackcsg" <nospam@xxxxxxxxxx> wrote in message =
news:1IKdnWfG6vr92KvfRVn-hA@xxxxxxxxxxxxxxx
> You can buy them with the resistors embedded, at 5 to 28vdc, some even =
to 60
> vdc. (I'm looking through my Newark Catalog), they draw 17 ma at 12 =
vdc. I
> know the Shack carries them...lord knows I've bought a few hundred
> there....(I love it when they ask me "what's it for?")
>=20
> "Crash Gordon=AE" <NONE@xxxxxxxx> wrote in message
> news:rdrZd.46$cp.1735@xxxxxxxxxxxxxxxxxx
> You'll have to knock the voltage down for the LEDs too..otherwise they =
make
> a nice crackly-popping sound as the plastic shoots across the room.
>=20
> I "think" from 12v to 3v is a 660 ohm resistor...to give you voltage
> drop...something like that.
>=20
>=20
> <me@xxxxxxxxxxx> wrote in message
> news:lr9c31t6t1qgvqiijck5m2v8fmslnst55b@xxxxxxxxxx
> > On Mon, 14 Mar 2005 17:35:52 -0500, "Jackcsg" <nospam@xxxxxxxxxx>
> > wrote:
> >
> > >It was simple until you said you wanted the LED to flash. Are you =
good
> with
> > >a solder gun? It is easily done, but it's going to be a little =
intricate
> if
> > >you're only a DIY'er. Do you want the buzzer to be intermittent =
with the
> > >LED, or a small steady buzz? The switches are easy because you can =
use a
> > >DPDT switch to "shunt" the alarm device.
> >
> > I think a small steady buzz.
> > Note that the CCTV DVR box has 8 wires all 500ma, 12volts each.
> > All 8 wires from CCTV DVR would go into one black box that is =
drilled
> > on the front, 8 LEDs, 8 switches (1 per sensor), and buzzer inside.
> >
> > There should be some way to handle the amp and voltage so it doesn't
> > go back and blow up the CCTV box.
> >
> > I've forgotten everything they taught me in science classes. If I =
had
> > a diagram I could show it to the people in Maplin.
> >
>=20
>