Star Tech Journal

Issue: 1981-January - Vol 2 Issue 11

S~R-TECH _ _ _ _ _ _ _ _ _ 3
Mechanical Maintenance Tips
for Williams' Pin Games
MECHANICAL MAINTENANCE
General Switch Blade Adjustments
There are different types of switch blades used in any
game. Various lengths, thickness and forms are selected
characteristics to satisfy specific operational conditions
(bounce, current capacity, etc.). For this reason, always
use a blade of the same type for replacement. Basic
guidelines for switch adjustments follow:
1. Never kink or bend a blade sharply; adjust with a
sweeping, bowing motion with a switch adjusting tool
or duckbill pliers.
2. Before adjusting any switch, check that the screw
holding the switch stack is tight. This is recommended
because spacers in the switch stack occasionally
shrink causing a poor adjustment.
3. Except when otherwise indicated, blade type switches
should have at least 1 /32 inch between open contacts
and have at least a 1 /32 inch follow-thru when closed.
4. First adjust the actuating blade for approximate
gapping and the other blade for the final gap and for
follow-thru.
Contact Care
1. Switch contacts should be cleaned only when they
cause a malfunction.
2. For flipper button and flipper end-of-stroke switches,
remove tarnish with a contact file and then burnish.
Severely burnt contacts should be replaced as an
assembly.
3. All other types of contacts MUST NOT be filed or
burnished.
4. To clean contacts of other blade type switches, close
the contacts on a clean piece of paper about the
thickness of a busines card and wipe gently until the
contacts are clean.
5. For drop target switches, remove the two screws
securing the circuit board. Clean the circuit board
plating with a rag and pencil eraser. Carefully clean
the wiper contacts with a burnishing tool- do not use
an abrasive.
Rollover Switches
Rollover Switches are activated by a wire form or button
which is actuated by the ball.
1. Before adjustment, make sure that the wire form
rollover is centered in the slot or that the switch blades
are positioned under the button actuator.
2. Adjust the long blade (closest to the playfield) to hold
the rollover up. Check this condition with the playfield
lowered.
3. With the playfield up, adjust the short blade for 1 /16
inch contact gap.
4. The backup blade (which prevents vibration) should
be adjusted parallel to and just barely in contact with
the shorter blade.
Tilt Switches
1. To make the plumb bob tilt more sensitive, raise the
plumb bob on the shaft. To make it less sensitive,
lower the bob on the shaft.
2. To make the ball roll tilt more sensitive, raise the
assembly at the front pivot slot. To make it less
sensitive, lower the assembly at the front pivot slot.
3. The slam tilt and playfield tilt switches are adjusted by
forming the switch blades.
Flippers
Flippers are controlled by the flipper pushbuttons at each
side of the cabinet. Each coil consists of two windings: a
pull-in winding and a lighter gauge hold-in winding. The
hold-in winding is normally bypassed by a closed switch.
The pull-in winding produces a strong stroke. However, if
this winding were to remain energized by the player it
would overheat. To reduce this high current, the hold-in
winding is put in series with the pull-in winding by
opening the end-of-stroke switch.
1. Adjust the long blade so that it is moved by the flipper
pawl assembly for about the last 1/s inch of movement.
2. Manually depress the plunger fully and adjust for
approximately 3/32 inch gap.
3. There should be about 1 /32 inch follow-thru with the
plunger released.
4. NEVER LUBRICATE the plunger.
5. For weak or sluggish flipper action, check for all the
following:
a. Dirty, pitted, or misadjusted flipper button or end of
stroke contacts.
b. Worn out coil sleeves.
c. Loose or broken bushing.
d. Worn out fiber links.
e. Weak or broken return spring.
f. Broken flipper shaft.
g. Coil loose.
h. Loose screws.
i. Flipper binding on plc!yfield.
4 _ _ _ _ _ _ _ _ _ _ Sl;q~TECH
Stern
"9 Ball" (Prototype)
Rom Mod
Problems:
1.
Lock-out problems (ball not
kicking out of lane, or outhold,
etc.) appear to be solved. (Left
lane is now run approximately
the same as the walker in
FLIGHT 2000. This should
correct all lock-out problems.)
2.
The game no longer gives out
random credits.
3.
Problems with SPECIAL award
not paying out when set to extra
ball corrected.
4.
Game now keeps correct High
Score to Date bookkeeping.
5.
Tilting the game while ball is in
left lane no longer locks up the
game.
6.
Add-a-ball feature now keeps
correct track of extra balls.
(Before it would only keep track
of 3, the 4th one would reset it
to 0.)
7.
Bonus multiplier now resets
correctly when threshold is
reached.
Cure:
Replace four original E PROMS
with updated 9 Ball V-60 U1, U2,
U5 and U6 E PROMS.
Contact your Stern Distributor
for availability or call Stern's
Customer Service WATS Line
Toll Free 800-621-6424.
Midway
"Space
Encounters"
Strobe Lite Unit
Subject:
Strobe lite unit -
PC-A084
91359-B645
Serial No. 101 to 3900
Please be advised that the
strobe lite printed circuit board
(Part number A084-91359-B645)
has been manufactured with the
wrong valued resistors and long
continuous play of the "Space
Encounter" game could cause
the resistors to overheat;
thereby creating a potential
hazardous condition.
Disconnect the plugs leading to
the strobe lite printed circuit
board. The plug is located in the
upper right hand portion of the
cabinet. It is easily accessible by
opening the top back door.
The "Space Encounter'' upright
game will operate properly even
though the strobe lite printed
circuit board is disconnected.
New strobe units will be shipped
to the Distributors for all "Space
Encounters" games.
D;
Midway
"Pac-Man"
Static Kit
Symptom:
STATIC
CONDITION
CAUSING A
FALSE
RAM AND ROM
TEST.
Solution:
Contact your distributor for
availability of "Pac-Man" Anti-
Static Kit PC A082-91389-A000
and install as per enclosed
instructions.

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