GRADE CROSSING DETECTOR
AND FLASHER
DF-1
211 RocBaar Dr., Romeoville, IL
60446
(815) 886-9010 FAX: (815) 886-9076
Electronics for Model Railroads
GENERAL DESCRIPTION:
The CIRCUITRON
DF-1
is an advanced, integrated circuit detection unit
with an alternating flasher contained on the same circuit board. The detection part of the circuit utilizes
CIRCUITRON’s proven Opto-Electronic system and provides true-prototype grade crossing for all
single
direction
applications. If your application requires Bi-directional detection, use a CIRCUITRON
DT-1
or
DT-
2
instead. The
DF-1
is entirely independent of the track power and may be used for all scales and
methods of power including AC track power and carrrier control systems. The flasher section of the
DF-1
will power two 250 ma. loads and may be used with either LEDs or incandescent lamps. Additional
CIRCUITRON detection units may be easily connected to the
DF-1
to control the flasher section in order
to provide detection on parallel tracks. An output terminal on the
DF-1
may be connected to additional
accessories such as the CIRCUITRON
ER-1
or
ER-2
External Relays or the
BR-1
and
BR-2
Bell Ringer
Circuits. The
DF-1
may be powered by any 10-18 volt AC or DC source.
INSTRUCTIONS:
The
DF-1
can be connected with .110" solderless connectors (available from
CIRCUITRON) or by soldering leads directly to the terminals on the printed circuit board. If soldering, use
a small pencil-type iron and electronics-grade rosin core 60/40 solder (available at Radio Shack). Use only
as much heat as necessary to obtain a good joint and do not wiggle the terminal until the solder has
cooled completely. A section of CIRCUITRON’S
PCMT
can be used for simple, snap-in mounting of the
circuit board or you may drill holes in the mounting pads in the corners of the board and mount the
DF-1
with screws and standoffs.
1) Mount the DF-1 in a convenient location. The
DF-1
should be mounted near the grade crossing on
the underside of the layout.
2) Mount the two Opto-Sensors following the instructions included with them. One Sensor should be
located where you want the approaching train to start the signals flashing, and the other should be
located just a short distance beyond the crossing.
3) Connect one lead on each Opto-Sensor together with light gauge (22-24 ga.) wire, and then run that
wire to the Sensor Drive Terminal
[SD]
on the circuit board.
4) Individual wires are then run from the remaining leads on both of the Opto-Sensors to the Sensor
Terminals
[S1]
and
[S2]
on the board. Make sure that the Opto-Sensor just past the crossing is
connected to
[S2]
.
5) Connect one side of all the lamps to be flashed at the crossing together and run a wire to the
[LAMP]
Terminal on the circuit board. If the signals you are using have LEDs, you must observe
proper polarity and include a current limiting resistor in this connection. Follow the instructions
supplied with your signals. The
[LAMP]
terminal on the circuit board is positive (+).
6) Connect the remaining leads from the RIGHT side lamps together and run a wire to the Right Flasher
Terminal
[R]
on the circuit board.
7) Connect the remaining leads from the LEFT side lamps together and run a wire to the Left Flasher
Terminal
[L]
on the circuit board.
CAUTION: The total lamp load connected to EITHER the
[L]
or
[R]
Terminal on the
DF-1
must never
exceed 250 ma.
8) Connect a 10-18 volt AC or DC source to the Input Terminals
[-]
and
[+]
. Observe proper polarity if
a DC source is used.
This completes the basic connections for the
DF-1
. If detection on parallel tracks is desired, use a
CIRCUITRON
DT-1
,
DT-2
, or
DT-3
and connect the output to the Control Terminal
[C]
on the
DF-1
. If
you
wish to use the
DF-1
to control additional devices such as relays or bells, connect a wire from the Output
Terminal
[OUT]
on the
DF-1
to the Control Terminal on the external device.
