----- Original Message -----
Sent: Monday, February 27, 2006 8:46
AM
Subject: [FlyRotary] Re: Fire Detector
Unit
If Acroname.com has the inventory on hand (no reason to
think
otherwise), it looks to be a good source for the UVTRON fire
detectors
and circuit boards. The question is can it run a good
sized LED without
needing a relay board. Output is 50v, so that
would have to be dealt
with (following Ed's recommendations). So,
it appears that a relay
board won't be necessary unless you're planning
on using a landing light
as a warning indicator. The C3704 is rated
for 10 - 30 volts input, so
that eliminates the need for the voltage
converter board. They have two
other models if you need a different
input voltage. The board would
need to be mounted in a project box
(readily available at Frye's) with a
window cut for the UVTRON to look
through. I used nylon screws from the
Home Depot avionics
department to mount the board.
From the picture on the Acroname web
site, it doesn't appear that the
board is protective coated. IMHO,
this should be done to improve
longevity and reliability. The
coating should be available from a
number of electronics suppliers, or
use something like epoxy resin or
E6000.
One other caution,
the UVtron operates at 350v, so be careful handling
it while it is
powered up.
All in all, it appears the single-board solution would be
a more elegant
solution, but would require some experimenting to get it
to do what we
want. We know that the 3-board solution works as
is. So, its up to
each to determine which option suits your
needs.
Since Bob Darrah had indicated he was interested in this item,
he's
agreed to order one of the boards and we will test it out to see if
it
will power an LED, and what additional components it needs to make
that
happen. I will report back to the group with the good, the bad
and the
ugly.
Mark
I agree that a relay board would not be needed (I didn't even
see it on the web site), however, it appears to me that it only puts out a
single pulse which can be stretched by adding a capacitor. If you
wanted more on time a latching circuit would be needed depending on your
alarm circuitry. An led could be driven off the open collector out put but
on time would be limited by the length of the pulse, hence the need for a
latching circuit. That's the way I see it.
Wendell