Beginners Guide To Candy Cabs

What is a Candy Cab?

Candy cab is the Western collector term commonly used for Japanese-style universal arcade cabinets, particularly the compact sit-down machines produced by manufacturers such as Sega, Taito, SNK, Namco, Konami and Capcom.

Typical characteristics include:

A metal or moulded plastic cabinet rather than the large wooden construction common to many Western arcade machines
A sit-down playing position
A CRT monitor, commonly between 18 and 29 inches
Interchangeable control panels
Universal game wiring such as JAMMA or later JVS
Operator access to the game PCB, power supply and monitor
A design intended to allow the installed game to be changed

Not every Japanese sit-down cabinet is technically a candy cab, and there is no single official Japanese cabinet category corresponding exactly to the Western term.

The precise origin of the term candy cab is uncertain. It is often associated with SNK's Candy cabinet range, which became familiar to Western collectors, but this derivation should not be treated as conclusively documented.

How much do they cost and where can I buy one?

Prices vary considerably according to:

Model
Condition
Originality
Monitor condition
Location
Rarity
Included control panels and accessories
Whether the cabinet is complete and working

The most desirable models can command significantly higher prices than common machines, particularly when fitted with an original monitor in good condition.

When buying a cabinet, useful things to check include:

Screen burn
Geometry and convergence
Monitor brightness and focus
Whether the monitor displays all required scan frequencies
Rust and water damage
Cracked plastics
Missing doors and locks
Original control panel
Original wiring loom
Power supply condition
Coin mechanism
Speaker condition
Internal modifications
Whether a step-down transformer is required

Cabinets are most commonly bought privately from other collectors, through arcade forums, specialist importers, auctions and group imports.

See the Marketplace and the "What's it worth?" discussion for current community pricing.

Are they easy to transport?

Compared with many traditional wooden upright cabinets, Japanese sit-down cabinets are relatively compact, but they are still heavy.

A typical cabinet may weigh approximately:

70-120 kg

although larger machines can weigh considerably more.

Common dimensions are roughly:

60-80 cm wide
70-95 cm deep
120-150 cm high

Many cabinets have rear wheels or casters and are designed to be tilted slightly for movement.

Depending on the model, the following may also be removable:

Control panel
Marquee
Monitor surround
Doors
Monitor
Upper cabinet section

Removing the control panel can make a substantial difference when moving a cabinet through a narrow doorway.

Always check the cabinet's centre of gravity before tilting it. Large CRT monitors make many cabinets extremely top-heavy.

What is JAMMA?

JAMMA is an arcade wiring standard associated with the:

Japan Amusement Machinery Manufacturers Association

The standard became widely adopted during the second half of the 1980s and uses a 56-pin edge connector.

The JAMMA connector carries most of the signals required by a conventional arcade game, including:

+5 V power
+12 V power
-5 V power
Ground
RGB video
Composite sync
Mono audio
Coin inputs
Start buttons
Joystick directions
Up to three action buttons per player
Test and service functions

Put simply, the JAMMA edge connector provides a standard interface between an arcade cabinet and a compatible game PCB.

This meant that operators could change games without rewiring the entire cabinet.

What is JAMMA+?

JAMMA+ is an informal collector/operator term rather than a separate universal standard.

It usually describes hardware which uses the normal JAMMA connector but requires additional connections for functions not provided by the basic JAMMA pinout.

Examples include:

Extra buttons
Stereo audio
Analogue controls
Multiple players
Additional power
Communication connections

Capcom CPS-series fighting games are a familiar example, using an additional harness for buttons beyond the three available through standard JAMMA wiring.

What is JVS?

JVS stands for:

JAMMA Video Standard

It is a later arcade interface standard developed for newer arcade hardware.

Unlike JAMMA, JVS does not use a single game-board edge connector for all cabinet functions.

A typical JVS installation may use separate connections for:

Video
Audio
Power
Controls
Communication

Controls are normally handled through a JVS I/O board connected to the game hardware by USB-style communication.

JVS systems commonly provide:

More control inputs
Analogue input support
Digital communication between the cabinet and game system
Stereo audio
3.3 V power support
Easier support for more complex control arrangements

Examples of arcade hardware commonly associated with JVS include:

Sega Naomi
Sega Naomi 2
Sega Chihiro
Sega Triforce
Namco System 246 / 256
Taito Type X-family installations

How do I run JVS games in a JAMMA cabinet?

An appropriate:

JVS-to-JAMMA I/O

can be used to interface JVS game hardware with a JAMMA cabinet.

Common examples include I/O boards produced by:

Sega
Capcom

The exact installation depends on:

Cabinet power supply
Audio arrangement
Monitor frequencies
Control configuration
Game hardware

Some JVS systems require substantially more current than a conventional JAMMA PCB and may need a separate JVS power supply.

Do not simply increase the cabinet's +5 V adjustment in an attempt to compensate for an inadequate power supply.

Excessive voltage can damage:

Game hardware
I/O boards
Wiring
Connectors

How do I run JAMMA games in a JVS cabinet?

A:

JAMMA-to-JVS I/O

can allow a conventional JAMMA PCB to be connected to a JVS cabinet.

Examples have been produced by companies including:

Namco
Konami
River Service

Video compatibility must also be considered.

A JAMMA PCB normally outputs approximately 15 kHz RGB video. If the cabinet monitor only accepts 31 kHz video, an upscaler or replacement monitor may be required.

What is a PCB?

PCB means:

Printed Circuit Board

In arcade terminology it usually means the game hardware itself.

Examples include:

A dedicated single-game PCB
A motherboard with interchangeable cartridges
A motherboard with interchangeable ROM boards
A disk-based arcade system

Examples of cartridge or modular arcade systems include:

Neo Geo MVS
Taito F3
IGS PGM
Sega ST-V
Capcom CPS-2

What monitor frequencies are used in arcade machines?

Three horizontal scan-frequency groups are particularly common in Japanese arcade hardware.

15 kHz — Standard Resolution

Usually approximately:

15.7 kHz

This is the traditional arcade video frequency used by the majority of classic JAMMA PCBs.

It is broadly comparable to the 240p/288p RGB video used by many contemporary consoles and CRT televisions.

Typical resolutions include:

320×240
384×224
256×224

The exact pixel resolution varies greatly between arcade systems.

24 kHz — Medium Resolution

Often called:

24 kHz

or historically:

medium resolution

The actual horizontal frequency is generally around 24-25 kHz.

It was used by certain arcade systems and games requiring a higher-resolution display.

Examples include some:

Sega System 24 games
Sega Model-series installations
Namco hardware
Mid-1990s dedicated machines

24 kHz support is much less universal than 15 kHz.

Some arcade monitors are:

15 kHz only
15/24 kHz dual-sync
24/31 kHz
15/24/31 kHz tri-sync

Never assume a monitor supports 24 kHz simply because it is fitted to a Japanese cabinet.

31 kHz — VGA Resolution

Usually approximately:

31.5 kHz

This corresponds broadly to 640×480 VGA timing.

31 kHz became increasingly common with late-1990s and 2000s arcade hardware such as:

Sega Naomi
Sega Naomi 2
Sega Chihiro
Sega Triforce
Atomiswave
Various PC-derived arcade systems

Some game systems allow the operator to select between 15 kHz and 31 kHz output.

Others are fixed to one frequency.

Always check the specific game hardware before connecting it to a monitor.

What is a dual-sync monitor?

A dual-sync monitor supports two arcade scan-frequency ranges.

Common examples include:

15/24 kHz
15/31 kHz
24/31 kHz

The exact combination depends on the monitor.

The term therefore does not automatically mean 15/24 kHz.

What is a tri-sync monitor?

A tri-sync arcade monitor supports approximately:

15 kHz
24 kHz
31 kHz

Frequency switching may be:

Automatic
Manual
Connector-selected
Switch-selected

Tri-sync monitors are popular because one cabinet can accommodate arcade hardware from several generations.

CRT monitors do not have a fixed native resolution in the same sense as LCD displays.

However, different monitor chassis and tube combinations may produce noticeably different:

Sharpness
Scanline appearance
Geometry
Focus
Colour
15 kHz presentation

Some collectors therefore prefer dedicated 15 kHz monitors for older games even when a tri-sync monitor is available.

Can I convert a dual-sync monitor to tri-sync?

Sometimes.

It may be possible to install a different monitor chassis onto an existing CRT tube, but compatibility must be checked carefully.

Important factors include:

Horizontal yoke resistance
Vertical yoke resistance
Horizontal inductance
Vertical inductance
Tube size
Tube deflection angle
Heater voltage
Neck socket
CRT pinout
Chassis operating voltage

A replacement chassis should never be assumed compatible simply because it physically connects to the tube.

Incorrect chassis/tube matching can damage the chassis and potentially the CRT.

How easy is it to rotate a monitor?

Many universal Japanese cabinets allow the CRT to be installed either:

Horizontal

or:

Vertical

This is commonly referred to as:

Yoko — horizontal
Tate — vertical

The difficulty varies greatly between cabinets.

On many machines the normal procedure involves:

Removing the monitor surround or bezel
Disconnecting or freeing any cables which restrict movement
Removing the monitor retaining bolts
Lifting or sliding the monitor assembly forward
Rotating the monitor 90 degrees
Reinstalling the monitor
Repositioning the bezel

A 25- or 29-inch CRT monitor can weigh several tens of kilograms.

Two people are strongly recommended unless the cabinet incorporates a dedicated rotation mechanism.

Rotation mechanisms

Some cabinets include mechanisms designed specifically to make rotation easier.

A well-known example is the:

Taito Egret II

whose monitor is mounted in a rotating assembly.

Other cabinets use assisted frames, rails or rolling mechanisms.

CRT safety

Arcade CRT monitors contain potentially lethal voltages.

Danger may remain present even after the cabinet has been disconnected from the mains.

Particular hazards include:

CRT anode voltage
Mains input circuitry
Large capacitors
Exposed monitor chassis
Fragile CRT necks

Do not work on an exposed CRT monitor unless you understand the appropriate safety procedures.

The CRT itself is also under vacuum and should be handled carefully to avoid damage or implosion.

What about picture adjustment?

Many arcade monitors use a remote adjustment board containing controls such as:

Brightness
Contrast
Horizontal position
Vertical position
Horizontal size
Vertical size
Red gain
Green gain
Blue gain

The exact adjustments available depend on the monitor chassis.

Additional controls may be located directly on the monitor chassis.

Older monitors may have most adjustments on the chassis itself, while some later monitors use an on-screen menu.

Do not adjust unidentified chassis controls at random.

Controls marked for functions such as:

B+
High voltage
Horizontal frequency
X-ray protection

may affect the monitor's operating conditions rather than simple picture geometry.

What is degaussing?

A CRT display can develop colour-purity problems after:

Being moved
Being rotated
Exposure to magnetic fields
Changes in orientation relative to the Earth's magnetic field

This often appears as coloured patches on areas which should be a uniform colour.

Most arcade monitors have a degaussing coil around the CRT.

Degaussing may occur:

Automatically at power-up
When a cabinet degauss button is pressed

External degaussing coils or wands can also be used when required.

Not every colour-purity fault is caused by magnetisation. Yoke alignment, purity rings, shadow-mask damage and other CRT faults can produce similar symptoms.

What is screen burn?

Screen burn is permanent uneven phosphor wear caused by displaying the same bright image for a very long period.

Common examples include:

Credit text
Score displays
Game logos
Playfield boundaries
Static backgrounds

Severe burn may be visible even with the monitor switched off.

Screen burn cannot normally be repaired without replacing the CRT.

When buying a cabinet, always ask about screen burn and, where possible, inspect the monitor displaying a bright uniform image.

What is convergence?

Convergence describes how accurately the red, green and blue electron beams meet at the same point on the CRT.

Poor convergence can appear as coloured outlines around:

Text
Sprites
Grid patterns
White lines

Some convergence error near the extreme corners of a large CRT can be normal.

Major convergence problems may indicate:

Yoke movement
Incorrect yoke position
Disturbed convergence strips
Incorrect purity/convergence ring settings
Tube or chassis issues

What is geometry?

CRT geometry refers to the shape and position of the displayed picture.

Common geometry faults include:

Bowing
Trapezoid distortion
Pincushion distortion
Uneven width
Horizontal or vertical shift
Corner distortion
Rotation

Some faults can be adjusted electronically.

Others depend on:

Yoke position
CRT construction
Magnetic correction strips
Chassis design

Perfect geometry across an entire large CRT is not always achievable.

Do I need a step-down transformer?

Many Japanese arcade cabinets were designed for:

AC100 V

mains input.

UK and European mains is approximately:

230 V

A cabinet designed only for 100 V must therefore not be connected directly to UK mains.

A suitable step-down transformer is normally required unless the cabinet has:

A multi-voltage transformer
A replacement European power supply
An internal 230-to-100 V transformer
Another documented mains conversion

Always check the cabinet's actual mains rating.

Do not assume a cabinet is still wired exactly as it left the factory.

Can I run a Japanese 100 V cabinet directly from US 120 V mains?

Do not assume that every Japanese cabinet or component is safe at 120 V.

Some Japanese equipment tolerates the difference, while other equipment may run hotter or operate outside its intended specification.

The correct approach is to check:

Cabinet rating
Transformer rating
Monitor rating
Power-supply input specification

A suitable 120-to-100 V transformer can be used where required.

What size step-down transformer do I need?

The transformer must be rated to comfortably exceed the cabinet's maximum expected load.

VA and watts are related but are not always directly interchangeable for AC loads.

For example, if a cabinet is labelled:

200 VA

do not choose a transformer rated exactly 200 VA.

Allowing additional capacity reduces heat and voltage drop.

The required size depends on the complete cabinet, including:

CRT monitor
Power supply
Game PCB
Audio amplifier
Fans
Lighting
Additional game hardware

Systems such as Naomi with GD-ROM hardware can require considerably more power than a simple JAMMA PCB.

What does the +5 V adjustment do?

Most traditional arcade game PCBs use a regulated:

+5 V DC

supply.

Voltage drops occur in:

Wiring
Connectors
JAMMA edge connectors

For this reason, the power supply may provide a small +5 V adjustment.

Voltage should ideally be measured at the game PCB rather than only at the power supply terminals.

Do not simply turn the adjustment upwards.

Excessive +5 V can permanently damage game hardware.

What about +12 V and -5 V?

Standard JAMMA also includes:

+12 V

and:

-5 V

The +12 V line is commonly used for:

Audio amplifiers
Motors
Other auxiliary circuits

The -5 V line is used by some older PCBs, particularly for certain audio circuits.

Many later games do not require -5 V.

Some modern replacement arcade power supplies omit it entirely.

Are control panels interchangeable?

Sometimes.

Many cabinet families use standardised panel dimensions within that family.

Examples include several Sega cabinets such as:

Astro City
New Astro City
Blast City
Net City
Versus City

Other manufacturers also reused panel formats across multiple machines.

However, similar-looking control panels are not automatically interchangeable.

Differences can include:

Overall dimensions
Screw positions
Panel curvature
Mounting brackets
Wiring connectors
Overlay shape

Always compare measurements before buying a replacement panel.

Which joysticks and buttons are normally used?

Two major Japanese arcade-control manufacturers are:

A typical Japanese control panel uses:

30 mm action buttons
24 mm Start buttons

Common joystick installations use either:

Individual microswitch connections
A five-pin joystick connector

Different joystick mounting plates are available, so physical compatibility should be checked before purchase.

What is a kick harness?

The standard JAMMA connector provides three action buttons per player.

Games requiring additional buttons use supplementary wiring.

Capcom's six-button fighting games made the term:

kick harness

particularly common.

The additional harness carries the fourth, fifth and sixth player buttons.

Different game systems use different auxiliary connectors.

For example:

CPS-1
CPS-2
CPS-3

do not all use exactly the same arrangement.

Other manufacturers also used extra-button harnesses.

What about Neo Geo MVS wiring?

Neo Geo MVS cabinet wiring is similar to JAMMA but not identical.

Depending on the MVS motherboard and cabinet configuration, differences can include:

Fourth action button
Game-select input
Stereo audio arrangements
Test/service wiring

Some MVS motherboards are closer to standard JAMMA than others.

Do not assume that every MVS motherboard should be connected to every JAMMA cabinet without checking the pinout.

What about Atomiswave?

Sammy Atomiswave uses a JAMMA-style interface but requires additional connections for some functions.

A fifth button can be provided using additional wiring.

As with any arcade system, check the specific wiring requirements before connecting it to a cabinet.

What controls are inside the cabinet?

Universal cabinets commonly contain operator controls behind the service door or coin door.

These may include:

Power switch
Test button
Service button
Degauss button
Volume control
+5 V adjustment access
Fuse
Additional connectors

Exact arrangements differ between manufacturers.

Test

The Test button normally enters the game's configuration or diagnostic menu.

Depending on the game, this may allow adjustment of:

Difficulty
Lives
Coin settings
Controls
Sound
Monitor test patterns
Input tests

Service

The Service button usually adds a credit without operating the coin mechanism.

On some hardware it is also used for menu navigation.

Degauss

The Degauss button activates the monitor's degaussing circuit where fitted.

Do not repeatedly operate the degauss circuit in rapid succession.

What about credits?

Credits may be added in several ways depending on the game and cabinet.

Options include:

Coin mechanism
Service button
Dedicated credit button
Free Play setting

Free Play may be configured through:

DIP switches
Test menu
Game software

Not all games implement Free Play properly.

Some games behave differently in Free Play mode, particularly in attract mode or multiplayer operation.

Can I use coins other than 100 yen?

Possibly.

Japanese cabinets commonly use 100-yen coin mechanisms, but coin mechs can sometimes be:

Adjusted
Replaced
Converted
Bypassed with a credit switch

The exact possibilities depend on the coin mechanism.

Do not permanently modify an original mechanism unless necessary, particularly on rare cabinets.

What is the difference between mono and stereo audio?

Standard JAMMA provides amplified mono audio through the edge connector.

Some later cabinets and game systems support stereo audio through separate connections.

Never assume that a stereo amplifier output can be connected directly to JAMMA speaker wiring.

Check whether the signal is:

Amplified speaker-level
Line-level
Mono
Stereo

Incorrect audio connections can damage amplifiers or game hardware.

What is an isolation transformer?

Some arcade monitor designs require an:

isolation transformer

between the mains supply and the monitor chassis.

Other monitor chassis incorporate isolation internally and do not require an external transformer.

Never bypass an isolation transformer unless the monitor documentation explicitly confirms that one is not required.

Doing so can create a serious electrical hazard and may damage equipment.

What is arcade RGB video?

Traditional arcade PCBs usually output analogue:

Red
Green
Blue
Ground
Sync

Arcade RGB signal levels are often higher than domestic SCART RGB levels.

Connecting arcade RGB directly to domestic video equipment may therefore require attenuation or an appropriate interface.

What type of sync do arcade monitors use?

Most JAMMA games output:

composite sync

where horizontal and vertical synchronisation are combined onto one wire.

Some monitors and game systems may instead use:

Separate horizontal and vertical sync
Positive sync
Negative sync

Compatibility depends on both the game hardware and monitor.

How do I swap a JAMMA game PCB?

A typical procedure is:

Switch the cabinet off.
Disconnect it from mains power if you will be working around exposed mains wiring.
Secure the PCB to an appropriate mounting board or tray.
Check the JAMMA connector orientation carefully.
Connect the JAMMA harness.
Connect any required auxiliary harnesses.
Check that no PCB or wiring can contact exposed metal.
Switch the cabinet on.
Measure the +5 V supply at the game PCB if necessary.
Enter the game's test menu.
Check controls and coin inputs.
Adjust game settings.
Adjust audio volume.
Display a monitor test pattern if available.
Adjust picture geometry and position using the normal monitor controls.
Install instruction cards or marquee artwork.
Secure the cabinet doors.

Never connect or remove a JAMMA PCB with the cabinet powered on.

What should I check before connecting an unknown PCB?

Before powering an unfamiliar arcade board, check:

JAMMA orientation
Connector condition
Burnt edge contacts
Short circuits
Correct power-supply voltages
Whether the board is actually JAMMA
Whether an adaptor is required
Whether -5 V is required
Whether extra buttons use a separate harness
Video frequency
Audio arrangement

Some older arcade boards pre-date JAMMA and can be damaged if connected directly to a JAMMA harness.

What should I check before buying a cabinet?

If possible, inspect the cabinet operating with a known-good game.

Check:

Cabinet

Rust
Cracks
Water damage
Missing doors
Missing locks
Bent control panels
Damaged wheels
Previous drilling or modifications

Monitor

Screen burn
Brightness
Focus
Geometry
Convergence
Colour purity
Stability
Correct sync
Chassis condition

Electrical

Correct mains voltage
Original or replacement PSU
Earth wiring
Damaged connectors
Burnt wiring
JAMMA connector condition

Controls

Joysticks
Buttons
Start buttons
Coin inputs
Test/service buttons

Originality

Check whether the cabinet still has its:

Original monitor
Original control panel
Original loom
Original PSU
Original doors
Original marquee
Original instruction holders

Replacement parts are not necessarily undesirable, but they can affect collector value.

Terminology

Common Japanese arcade-cabinet terminology includes:

Term	Meaning
Candy cab	Western collector term for Japanese-style universal sit-down arcade cabinets
JAMMA	Standardised arcade PCB/cabinet interface
JVS	Later JAMMA Video Standard interface
PCB	Printed Circuit Board; commonly the arcade game hardware
Yoko	Horizontal monitor orientation
Tate	Vertical monitor orientation
15 kHz	Standard-resolution arcade video
24 kHz	Medium-resolution arcade video
31 kHz	VGA-resolution arcade video
Dual-sync	Monitor supporting two scan-frequency ranges
Tri-sync	Monitor supporting approximately 15/24/31 kHz
Kick harness	Additional control wiring beyond standard JAMMA
Screen burn	Permanent phosphor wear caused by long-term static images
Degauss	Demagnetisation of a CRT display