silicon to prevent water from leaking inside. Note in the
schematics (Figure 18 and Figure 19) that the DS1620
does not have a capacitor or resistor connected to it. The
DS1620 connected to the Atom with a cap and resistor
like a BASIC Stamp uses will not give an accurate
temperature reading if those components are installed.
■ FIGURE 15
■ FIGURE 16
Display of time and date, as well as a data log of
temperatures, is set by the DS1302 clock chip. The clock
IC is mounted inside the remote slave display case upstairs
(Figure 20). Refer to the schematic (Figure 19) for wiring
details. The indoor DS1620 and the DS1302 are mounted
on a small universal protoboard (Figure 16). Use an
external battery to store clock time in the event of a
■ NOTE: DO NOT use a capacitor or resistor on
DS1620 when using Atom microprocessors.
house area). Slowly open the damper until the smoke stops.
This is the minimum that you ever would want the damper
closed while the fire is operating. Attach the push-pull tube
or adjust your linkage at this position so that the closed limit
switch is activated. In my application,
this is approximately 25 degrees open.
■ FIGURE 18
DS1620 Indoor and
The indoor DS1620
temperature chip is mounted on
the slave circuit board (Figure 16).
For the outdoor DS1620 sensor,
the PCB (Figure 17) is mounted
inside a plastic construction box
(Figure 3). The edges are sealed with
■ FIGURE 17
■ FIGURE 19