Deltronic 1275 Ticket Dispenser
Despite the fact that
the ticket dispenser is a fairly simple device a regular
maintenance is required to ensure its reliable operation.
The most common ticket dispenser is the Deltronic ( DL
1275) ticket dispenser. The connection to the machine is
very simple. A four wire connection is all what is
required. Ground (black wire), +12V (red wire), notch
output (blue wire), motor drive input (white wire).
The machine will drive the motor drive
input "high" in order to switch the motor
"ON". The motor driver transistor (NPN
Darlington driver transistor) will turn "ON"
and will connect ground to the motor. Note that the other
side of the motor is connected to the +12V.The motor will
turn and keep dispensing the tickets as long as the drive
input is held "high". The tickets are passing
through the opto interrupter (opto switch) which detects
the notches on the edge of the tickets. Every notch
creates a pulse which is further conditioned by a CMOS
Schmitt Trigger IC Inverter (4584 or 40106) and an open
collector transistor (2N2222 or 2N4401). These pulses are
fed back to the game computer. Each dispensed ticket
creates one pulse.
The game computer counts the pulses and
will keep dispensing the tickets until the the number of
pulses received will be equal to the number of tickets
the game computer intended to dispense. Then the motor
drive input will be driven "Low" and the
dispensing will stop. In order to prevent any part of the
ticket to be dispensed after the motor is switched
"OFF" the motor must stop suddenly. A brake
transistor connected across the motor ensures that.
Without it the motor would keep turning for brief time
dispensing a portion of the ticket.
The brake transistor takes no part in
switching the motor "ON". It only acts briefly
when the motor is switched '"OFF". As the motor
tends to continue spinning, it becomes a dynamo
generating power. The brake transistor turns
"ON". The current flowing through the brake
transistor and the motor creates a magnetic field, which
will bring the motor to a sudden stop.
The failure to detect the notch is
probably the most common problem. The opto switch gets
obstructed by the dust created from the paper fiber and
must be regularly cleaned. A paintbrush used just for
this purpose works well.
Check the opto switch with your
multimeter. Measure the voltage on the notch output (blue
wire) against the ground (black wire). You should measure
5V with the opto switch obstructed and below 0.7V with
the opto switch cleared. If the notch output stays on 5V
no matter what you do with the opto switch, clean the
opto and retest it. If it is still not okay the opto
switch may need to be replaced. If the notch output
measures 0V with the opto switch obstructed , it may mean
the notch output is not connected to the game board
input. Check this connection. The 5V comes from a pull up
resistor which is a part of the game board input.
We also need to make sure that the
tickets are passing through the opto switch. A spring
blade mounted in opposite of the opto switch pushes the
tickets toward the switch. Make sure that there is enough
tension but not more than it is necessary.
WHAT WILL HAPPEN IF
THE MACHINE DOES NOT RECEIVE THE NOTCH FEEDBACK?
It will depend on the game software.
Most machines will let the ticket dispenser run for brief
time and if the notch is not received they will turn the
motor off. Usually four tickets are dispensed. So, if
someone complains that four tickets are dispensed no
matter what score has been reached, you know what to look
for. In some rare instances the game software does not
treat this condition very well and the machine may leave
the motor turned on and thus dispense all of the tickets.
Keep the mechanism clean, free of dust
and ticket leftovers. Keep all screws tight.Check the top
and the bottom ticket guides. Older dispensers may need
to be upgraded with new metal guides and transporting
rollers. The new metal guides are not only stronger but
they also have a different shape and protrude from the
slot in the front plate. This eliminates ticket jamming
on the front plate.Make also sure that the top spring has
enough tension to ensure good grip of the ticket.