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Document Title: [woodcock_tempest_repair.txt (text file)]

Troubleshooting your Tempest Machine, by Gregg Woodcock
This article is Copyright worldwide 1991, 1995; all rights reserved.

This is a file I have put together which should get you started on
repairing your non-working Atari Tempest game.  It lists all the
problems I have seen and lots of information from the various manuals.
Monitor failures are much more common than game board failures (in fact,
I find the game boards to be fairly robust) and that topic is so lengthy
that it is covered in another file.  The last portion of this document
includes the self-test instructions and DIP switch settings from the
manuals so you might want to start there.

Let me start out by stating that arcade games in general tend to have a
lot of problems with safety interlock switches which shift position or
deteriorate so that they no longer close all the way (to be fair to the
interlocks, sometimes it is the cabinet that warps pulling the engaging
panels away from the interlocks).  If you get no power at all and have
checked the fuses, make sure you check the safety interlocks to make
sure they are all engaged and conducting.  Also check for breaks in the
wall cord as these get a lot of yanking and abuse.  Replace the plug if
the earth ground pin is broken off.  Another good idea when you are
making repairs is to install high-quality sockets when you replace any
IC.  If it went bad once, it is likely to go bad again and you can save
time, effort and heat stress to the PCB by performing a solderless
replacement the next time it goes bad.

If you have a Tempest game board that doesn't seem to be working, check
to make sure the game isn't paused!  I have seen several boards come my
way that were "broken" but merely had the pause switches set.  The game
instantly "locks up" and you never get a picture or any response to
inputs and the spot killer lights; all symptoms of game board failure
which fools many people.  Before you assume you have a game board
failure, be sure that switches 1, 2, 7 and 8 on the 8-toggle DIP swtich
bank at location N13 are NOT set to Off, Off, Off and On, respectively;
this combination is marked "Demonstration Freeze Mode" in the
documentation and pauses the game.  As far as I know, no other Atari
game of any era has a pause switch in it but I wish they all did; it is
very handy for those marathon sessions when nature calls!

The first thing to check when you have a known good monitor and a game
PCB that does not produce video is the adjustment potentiometers.  I
recently spent a whole weekend verifying the vector generator circuitry
on a Tempest PCB only to find a hairline separation of the leftmost pin
(when looking at the side of the pot with the dial) of R168 (Y SIZ).
When this pin is floating, the spot killer kicks in and there is no
video at all!  When being improperly stored or transported, these
components take a lot of abuse and are bent back and forth.  Too much of
this and the legs simply break (usually only 1 at a time so it isn't all
that obvious).  Occasionally these cheap pots will simply go bad and
fail to work (yielding a permanent 0 or infinite resistance) so you
might check their resistance range with a multi-meter even if all the
pins are OK.  Simply replacing that 1 pot fixed my board.  When
replacing these pots, I lay them flat against (parallel with) the PCB to
lower their profiles so that they stick out less.  This problem can
happen on any Atari vector game; black-and-white or color.

The other common cause for a board with no video is a failure of the
AM6012 digital-to-analog converters that feed the X and Y sections of
the vector generator circuitry (1 chip for each signal).  If your game
has scraggly vectors that start out OK but get messed up as the game
warms up or if your vectors are totally trashed (particularly if it is
only in 1 dimension), you are probably observing the effects of a bad
DAC.  Of course if you let the symptoms continue, the DACs will fail
altogether and you will have no video at all (since the spot killer will
kick in).  The best way to check these is by using cold spray to
stabilize the DAC.  If you spray the chip and the game clears up then
you know that chip is failing (this works for any IC).  Otherwise you
could remove the old DAC and replace them with a known good DAC from
another board (installing sockets in the process).  Similar video
symptoms can occur as a result of less frequently failing parts such as
the LF13201 analog switches and the TLO84 op amps.

All Atari games of the early era were subject to bad solder joints and
this should always be the first place you start checking when you have
problems.  I know for a fact that most of the monitor failures in the
field are not due to overheating (at least not directly) but due to
lockups in the game board which cause the monitor to saturate and
overheat its semiconductors.  There are 2 boards that comprise the
Tempest board set.  The larger of them is about 2 feet long by 1 foot
wide and is known as the "vector generator PCB".  It contains all the
game ROMs, among other things.  The other smaller board is about 1 foot
square and is known as the "math box".

The most common cause of lockups and resets is bad solder joints on the
interbaord connector that lets these boards communicate with each other.
Whenever I get a new board set, I resolder these whether they look like
they need it or not.  The next most common cause is bad circuit board
edge connectors on the wiring harness.  If they are marginal at all, do
yourself a favor and replace them!  They can be cleaned fairly well by
spraying them with "tuner cleaner" (available at Radio Shack) and then
reseating the connector a few dozen times but this is only a temporary
solution because the real problem isn't so much dirt as poor tension due
to age and heat stress (and poor initial quality).  Similar problems are
common with the fuse holders in the power supply, particularly F2.  F2
is rated at 20 amps and ultimately feeds the +5 supply.  It can get
overheated and loose spring tension and this will cause resets.  This
can usually be fixed by cleaning and bending the clips tighter which
avoids having to replace the holders.

Two of the socketed 40-pin chips on the math box (locations B/C2 and
C/D2) are called "Audio I/O N-Channel MOS/LSI Custom Chips" by the
manual but at least the schematics refer to them by their "real" name
which is "POKEY".  The most frequent thing to go bad on the Atari math
boxes besides the ROMs are these POKEY chips.  The POKEY was designed by
the Atari home computer division for the Atari 400 computer.  It stands
for POt KEYboard controller and it has a sound generator, random number
generator, input buffering, and much more all on one chip.

The symptoms of a bad POKEY are that control input or sound output is
not normal or missing altogether.  The POKEY in Tempest at B/C2 controls
the spinner inputs so if your spinner is flakey and the opto-electronics
check out (they frequently fail), this is probably your culprit.  The
self test should be able to confirm the diagnoses.  If you see a "P" or
"Q" in the middle of the screen then one of the POKEYs is bad (see chart

I like to order POKEYs from American Techna-Vision since you get an
entire 40 PIN chipset intended for machines in the Atari 8-bit computer
line.  Besides the POKEY, you get a GTIA, ANTIC, and PIA.  Order catalog
number AK675, "40 Pin Large Scale Integrated Circuit Chip Set".  On top
of that they have the cheapest shipping, no minimum order (that I am
aware of) and accept credit cards.  You can also scavenge POKEYs from
inside of many Atari 7800 cartridges, most notably Ball Blazer although
they are also used in Commando and Summer Games and I suspect that Dig
Dug, Dark Chambers and Jinks also have one.  The POKEYs are the chips
that have the Atari part number "C012294B-01" on them.

B & C ComputerVisions
5917 Stope Wway 
El Dorado, Ca. 95623
(530) 295-9270 FAX 9271
E-mail myatari2@myatari.com
Web site: www.myatari.com
atari pokey our part# ICA294 $5.each
shipping 1 to 100 $8.00

Best Electronics        408.243.6950 (Atari POKEYs $5+$? S/H+$4.75 COD; $12 min)
American Techna-Vision  510.352.3787 (Atari POKEYs $5; #AK675)

The other 4 socketed 40-pin chips on the math box (at locations E2,
F/H2, J2 and K/L2 on Tempest) are called "transistor array"s by the
manual and the chips themselves carry only the Atari part number
137004-001 on them in an attempt to hide their true identity (to keep
people from making illegal copies of the game?)  They are really 2901
bit-slice ALUs, which were very popular and are fairly commonly
available.  They were made by AMD and a number of other vendors.  In a
technical sense the part really is a transistor array, but calling it
that serves no purpose other than obfuscation.  These go bad every now
and then and will generate an "M" on the self-test screen.  NOTE:  the
"M" is a generic "M"ath box failure indicator and does not necessarily
indicate that an ALU is bad; lots of failures cause the "M" indicator to
appear but one of the most frequent causes is bad ALUs.  The cheapest
place I have found for these is:

B.G. Micro, Inc         800.276.2206 (2901 AMD brand ALUs $0.55 each)

From page 6 of TM-190, 2nd printing, "Tempest Operation, Maintenance and
Service Manual"


     This game will test itself and provide data to demonstrate that
the game's circuitry and controls are operating properly.  The data is
provided on the monitor and the game speaker; no additional equipment
is necessary.

     Part 1 of the self-test procedure includes a display of the
operator-selectable game options, and game time and high score table
information.  Part 2 includes ROM and RAM, control panel and monitor

     We suggest you run the self-test procedure any time you collect
money from the game or any time you change the game's options.  Refer
to Figure 5 for location of the self-test switch and option switches.
To run the self-test, follow the instructions outlined in Figure 6.

Figure 5:  Location of Self Test Switch, Volume Control and Option
Switches.  [NOTE:  I will not attempt to draw the pictures but will
describe in detail what they show.  One shows the bottom of the front of
the machine with the coin door wide open.  An arrow points to a
rectangular assembly which juts out into the from the *inside* of the
cabinet located about 1/3 the way down the left side of the opening.
There is a blow-up of this area which shows that this rectangle consists
of a volume control potentiometer which increases as you rotate
clockwise and also shows a slide toggle self-test switch for European
games.  US games have the self-test switch in the standard location for
most of Atari's early games.  Look in the very upper-right corner
(towards the hinge) of the interior of the coin door and you will find a
switch with a long stem.  The last picture shows the location of the
game PCBs which are in the middle of the back of the machine mounted on
the right (looking from the back) side panel.  There are 3 DIP switch
packs on the big game board ("vector generator PCB") and 1 on the small
one ("math box").  DIP switch packs are located at K10/11 (4 switches),
L12 (8 switches), and N13 (8 switches).  Together these 3 packs are
labeled "Options Switches".]


     The information below is displayed on the screen if you set the
self-test switch to on during the attract mode [i.e. after the game has
been turned on].  Look at the displayed numbers for SECONDS ON and
SECONDS PLAYED.  If these numbers run together vertically, make
adjustments to the X and Y outputs of the game PCB [particularly the
BIP controls].

     To go to the Self-test Part 2, rotate the control knob until the
monitor.  Then press both FIRE and SUPERZAPPER.  To end the operator
information display, set self-test switch to off.

                  +------------------------------------------+  TIME GAME
                  |                                        /--- PLAYED (Seconds)
   (Seconds) ----------\                                 /   |  NO. OF 1-
                  |     \----> 1158 SECONDS ON          /  /--- PLAYER GAMES
   SWITCH         |               0 SECONDS PLAYED <---/  /  |
   TOGGLE 1 ------------\         0 1 PLAYER GAMES <-----/   |  NO. OF 2-
                  |      \        0 2 PLAYER GAMES <----------- PLAYER GAMES
   COIN MECH      |       \       0 SECONDS AVERAGE <---\    |
   MULTIPLIER ----------\  \----+             +-----\    \----- AVERAGE
                  |      \----->|X11          |      \       |  GAME TIME
   ALL 8:         |             |BONUS ADDER 0|<---\  \      |
   SWITCH AT N13  |             v             v     \  \     |  SWITCH
   (Coin Modes) --------------> 0 0 0 0 0 0 0 0      \  \------ TOGGLE 8
                  |                                   \      |
   SWITCH AT L12 -------------> 0 0 0 0 0 0 0 0        \------- BONUS ADDER
   (Game Play)    |                                          |
                  |             0 0 0 0 0 0 0 0 <-------------- LAST 4:
                  |                                          |  SWITCH AT D/E2
   LIVES          |             _    _    _                  | (Game Difficulty)
   PER GAME -----------------> < >  < >  < >  MEDIUM <--------- GAME DIFFICULTY
                  |                                          |
                  |                                          |
                  |                                          |
                  |                                          |
                  |             (c) MCMLXXX ATARI            |
   NO. OF         |             BONUS EVERY  20000           |
   CREDITS ------------> CREDITS 1      1 COIN 1 PLAY <-------- COIN MODE
                  |                                          |

                          OPERATOR INFORMATION DISPLAY

To erase High Score Table:
1. Turn control knob until top line reads PRESS FIRE AND START 2 TO ZERO
2. Press both FIRE and START 2.
3. The word ERASING appears and blinks on the screen until the entire
   table is erased.  WAIT UNTIL THE WORD ERASING DISAPPEARS before
   continuing with other tests.

To erase Game Times:
1. Turn control knob until top line reads PRESS FIRE AND START 1 TO ZERO
2. Press both FIRE and START 1.
3. The word ERASING appears and blinks on the screen until the entire
   table is erased.  WAIT UNTIL THE WORD ERASING DISAPPEARS before
   continuing with other tests.


Instruction 1:
Set self-test switch to ON (see figure 5).  Press RESET on the PCB, or
turn power off and on again.

Test 1 Passes:
After about 5 seconds, the monitor displays the picture below.  No
sounds are produced

                  |   +---                                   |   ENTIRE WHITE
   ROM AT R1      |   |   |                                  |   FRAME VISIBLE
   IS BAD ----------> +---                                   |<- AND WITHIN 1/2
                  |   |   |                                  |   INCH OF
                  |   +---                                   |   MONITOR EDGE.
                  |   \   /                                  |
                  |    \ /                                   |
                  |     X                                    |
                  |    / \                                   |
   AUDIO 1 IS BAD |   /   \       +---                       |
   (Pokey at B/C2 |               |   |                      |
   on Math Box) ----------------> |---                       |
                  |               |                          |  TOGGLE
   TOGGLE ----------------------+ |           +---------------- SWITCH 8
   SWITCH 1       |_____________|_____________|______________|
                  |             v             v              |  SWITCH AT L12
   SWITCH AT N13 -------------> 0 0 0 0 0 0 0 0        /------- (Game Play) 
   (Coin Modes)   |                                   /      |
                  |             0 0 0 0 0 0 0 0 <----/  /------ SWITCH AT D/E2
   START 1 ---------------\                            /     | (Game Difficulty)
                  |        \    0 0 0 0 0 0 0 0 <-----/      |
   START 2 --------------\  \-----\       /-------------------- SUPER ZAP
                  |       \------\ \     /            _      |
   FIRE ----------------\       0 0 0 0 0 0 0 0      /_\  <---- CONTROL KNOB
                  |      \-----------/               | |     |
   SLAM SWITCH --------\        0 0 0 0 0 0 0 0 <-------------- RIGHT COIN
                  |     \--------------/ /   \               |
   LEFT COIN ---------------------------/     \---------------- CENTER COIN

RAM FAILURE is indicated by a sequence of 1 to 12 tones and an R
displayed in top half of screen.  You will hear a short low tone and see
a short flash on the LED start pushbutton for each good RAM chip, and a
long high tone accompanied by a long pulse on the start pushbutton for a
failing RAM chip.  The test stops with the first failing RAM.  To
restart the sequence, press RESET on the PCB, or power game to OFF then
to ON again.  Identify the bad RAM chip with the table below.  Example:
four short low tones followed by a long high tone indicates failure of
RAM at location M3.

================   ======================================================
       1st                                   R2
       2nd                                   P2
       3rd                                   R4
       4th                                   P4
       5th                                   M3
       6th                                   M4
       7th                                   L3
       8th                                   L4
       9th                                   K3
      10th                                   K4
      11th                                   J3
      12th                                   J4

ROM FAILURE is indicated by a vertical pair of hexadecimal numbers on the
top of the screen.  The top number indicates the location of the failing
ROM(s).  Ignore the bottom hexadecimal number in the pair.  Identify the
bad ROM with the table immediately below.

===============   ======================================================
      B                                     R1
      A                                     P1
      9                                    N/M1
      8                                    L/M1
      7                                     K1
      6                                     J1
      5                                     H1
      4                                     F1
      3                                     E1
      2                                     D1
      1                                     R3
      0                                    N/P3 *

EAROM, AUDIO AND MATH BOX FAILURE are indicated by a single letter in the
center of the display.  Identify the failure with the table below.

==================   ============   ==================
        E                EAROM        C3 (Aux. PCB)
        P               AUDIO 1      B/C2 (Aux. PCB)
        Q               AUDIO 2      C/D2 (Aux. PCB)
        R                 RAM       See RAM test above
        M             MATH BOX **

* If this ROM is bad, you will hear a continuous low tone, and the program
may be unable to display a screen.
** Math-box failure is explained in TM-195, Tempest Troubleshooting Guide.

Instruction 2:
Activate start, fire, Superzap, SLAM, and coin switches (activate coin
switches by inserting at least one coin in each coin slot.  You will not
trip the coin counters as long as you are in self-test).

Test 2 passes:
As switch activates, you'll hear a beep and 0 changes to 1 on the

You will not hear a beep and 0 will remain on the screen for the
defective switch.

Instruction 3:
Rotate encoder wheel clockwise and counterclockwise.

Test 3 passes:

The right hexadecimal number on the screen will increase with counter
clockwise motion, and decrease with clockwise motion.  [NOTE:  If your
board has EPROM 136002-117 at location J1 instead of 136002-217, you
will see a straight line that behaves like the second-hand of a watch
rotating around one end in the same direction that you spin the control
knob instead of seeing the hexadecimal numbers 0-F.]

The -217 EPROM
removes the high score backdoors.]

Incorrect [opposite] progression of numbers indicates encoder wheel
harness wires were connected incorrectly.  No number change indicates
encoder wheel [optos] is bad or harness wires are loose [or POKEY is

Instruction 4:
Observe the white frame around the outside of the screen.

Test 4 passes:
Each frame corner should be within 1/2-inch of each monitor bezel

See Tempest Drawing Package [or my other file on how to repair the
monitor] to adjust video pots.

Instruction 5:
Activate SLAM [tilt] switch.

Test 5 passes:
A white cross hatch pattern appears.  A character set appears at the
bottom of the screen.

If display is not centered and symmetrical on the monitor, adjust video
pots (see Tempest Drawing Package [or my other file on how to repair the
monitor]) on the main PCB.  If character set is incorrect, check Vector
ROMs (see Troubleshooting Guide).

Instruction 6:
Activate SLAM [tilt] switch.

Test 6 passes:
Horizontal and Vertical lines cross in the center of the screen
displaying a large "plus" sign.  Audio I/O 1 and 2 alternate to produce
4 tones.

Lines not crossing indicates [BIP] video pot[s] on main PCB needs
adjusting (see Drawing Package [or my other file on how to repair the
monitor]).  No sound indicates failure of an audio amplifier and/or the
custom audio chip(s).

Instruction 7:
Activate SLAM [tilt] switch.

Test 7 passes:
Tests purple, cyan, yellow, white, green, blue, and red for color and
intensity.  Displays seven groups of vertical lines, each with right
line the brightest and left line the dimmest.

Use this pattern for tracking adjustments (see the Color X-Y Monitor
Manual [or my other file on how to repair the monitor]).

Instruction 8:
Activate SLAM [tilt] switch.

Test 8 passes:
A checkerboard pattern touches the sides and corners of the monitor.
Rotate the control knob to change color.

Use this pattern for purity and convergence adjustments (see Color X-Y
Monitor Manual [or my other file on how to repair the monitor]).

Instruction 9:
Activate SLAM [tilt] switch.

Test 9 passes:
A white frame is displayed on the screen.

Perform math-box signature analysis (see Troubleshooting Guide).

Instruction 10:
When satisfied with test, set self-test switch to OFF position.


1.  Bonus Play Feature

     Tempest (TM) offers a bonus play for certain combinations of coins
inserted.  This bonus feature is operator-selectable, meaning you may
choose to offer it or not.

     With your game set at 25 cents per play, players who deposit four
successive quarters or a $1.00 coin, then press the start button, can
receive a bonus play.  Therefore, players can receive 5 plays for $1.00.

     This bonus feature encourages players to insert more money than
just the minimum 25 cents required for one game.  Various other bonuses
are also available (see Figure 8).

From TM-190; 2nd printing:


     To change toggle positions on the switch assemblies, you need not
remove the game PCB.  The switches are accessible when the Tempest (TM)
Analog Vector-Generator PCB is mounted in place.  To change positions on
the Auxiliary PCB slide the board out as far as possible.

     When changing the options, verify proper results on the monitor
display by *performing the self-test*.  Note that changing an option on
any of the following eight toggles will *not* cause an immediate change
on the monitor screen during the attract mode.

Settings of 8-Toggle Switch on Tempest Analog Vector-Generator PCB (at L12)
 1   2   3   4   5   6   7   8   Option
                            On   1-credit minimum $
                            Off  2-credit minimum

                    On  On       English $
                    On  Off      French
                    Off On       German
                    Off Off      Spanish

                                 Bonus life granted at every:
        On  On  Off              10,000 points
        On  On  On               20,000 points $
        On  Off On               30,000 points
        On  Off Off              40,000 points

        Off On  On               50,000 points
        Off On  Off              60,000 points
        Off Off On               70,000 points
        Off Off Off              No bonus life

Off Off                          2 lives per game
On  Off                          3 lives per game $
On  On                           4 lives per game
Off On                           5 lives per game

Settings of 4-Toggle Switch on Tempest Auxiliary PCB (at D/E2)
 N                               Game difficulty*
 O      On  On                   Medium $
 T      On  Off                  Easy
        Off On                   Hard
 U      Off Off                  Medium
 E  On                           Minimum rating range: 1,3,5,7,9 $
 D  Off                          Minimum rating range tied to high score
$ Manufacturer's suggested settings

* Easy - Enemies move slower and one less enemy shot on the screen at
         one time.
  Hard - One more enemy, enemies move faster and 1-4 more enemy shots on
         the screen at one time.

For pricing for "credits," see Figure 8.
Changing toggles 1-5 erases the high score table.


     The table below contains the switch settings for those options
relating to game price, coin mechanism multipliers, bonus play,
demonstration and freeze mode.  This information is useful if you want
to view all 99 levels of play or freeze the action, if you need to
temporarily set the Tempest (TM) game on free play, or if you have
German coin mechanisms in your door.

     To achieve bonus plays, all coins must be inserted before pressing
the start button.  If you choose the two play minimum, set toggle 8 at
PCB switch assembly L12 to *off*.

     The Demonstration Mode** allows you to choose any level (1-81) in
the ready-to-play mode and accelerate through the tubes without having
to kill the enemies.  Freeze allows you to stop the action.  The score
is zeroed at the end of the game in this mode.

     Set the toggles per the table below for the Demonstration Mode.
Next rotate the control knob.  You may choose level 1 through 81 during
the ready-to-play mode.  Press either START button to accelerate through
the tubes.  Press the FIRE button to clear the spikes at the bottom of
the tube.  To freeze play, set switch 1 to off.

Toggle Settings of 8-Toggle Switch on Tempest
    Analog Vector-Generator PCB (at N13)
 1   2   3   4   5   6   7   8   Option
                        Off On   Free play
                        Off Off  1 coin* for 2 credits
                        On  On   1 coin* for 1 credit $
                        On  Off  2 coins* for 1 credit

                 On  On          Right coin mech x 1 $
                 On  Off         Right coin mech x 4
                 Off On          Right coin mech x 5
                 Off Off         Right coin mech x 6

            On                   Left coin mech x 1 $
            Off                  Left coin mech x 2

On  On  On                       No bonus coins $
On  On  Off                      For every 2 coins*, game adds 1 more coin*
On  Off On                       For every 4 coins*, game adds 1 more coin*
On  Off Off                      For every 4 coins*, game adds 2 more coins*

On  On  On                       For every 5 coins*, game adds 1 more coin*
On  On  Off                      For every 3 coins*, game adds 1 more coin*

             Demonstration and Freeze Mode**
On  Off                 Off On   Demonstration Mode
Off Off                 Off On   Demonstration-Freeze Mode
* In the U.S>, a "coin" is defined as 25 cents.  In Germany, a "coin" is
  1 DM.
$ Manufacturer's suggested settings
** If you press RESET during this mode, game will lock up.  To recover,
   set switch 1 to on.


[These toggles determine which coin mechanisms activate which counters]
Toggle settings of 4-Toggle
 Switch on Analog Vector-
  Generator PCB (K10/11)     Two coin acceptors      Three coin acceptors
 4   3   2   1                in the coin door:       in the coin door:*
        On  Off  Both acceptors activate all     Left acceptor activates one
 N   N           coin counters simultaneously.   coin counter; center and
 O   O                                           right acceptor activates
 T   T                                           another coin counter.  /Not
                                                 for any currently designed
 U   U                                           3-mech coin door/.
 S   S
 E   E  Off On   Both acceptors activate 2       Left and center acceptor
 D   D           counters separately. $$         activate one coin counter;
                                                 right acceptor activates
 N   N                                           another coin counter.
 O   O
 T   T  Off Off  Both acceptors activate 2       Left, center and right
                 counters separately. $$         acceptors activate 3 coin
 U   U                                           counters separately. $$$
 S   S
 E   E  On  On   Both acceptors activate all     All 3 are same denomination
 D   D           coin counters simultaneously. $ and they activate all coin
                                                 counters simultaneously.
$ Manufacturer's suggested settings for games with 1 coin counter.
$$ Manufacturer's suggested settings for games with two coin counters.
$$$ Manufacturer's suggested settings for games with optional second and
    third coin counters.
* See Drawing Package DP-190 for additional components required for
  operating the third coin counter.