The household mains electricity supply is an alternating current (AC) that can
be described with two parameters: the voltage (in volts) and the frequency
(in Hz).

In North America, the standard household wall outlet offers 120 V/60 Hz power.
In much of the rest of the world, the mains is now standardizing to
230 V/50 Hz.  In the time of 8-bit Atari computers, most of continental Europe
used 220 V/50 Hz, and the UK used 240 V/50 Hz.

In any case, the household alternating current must be converted to a
direct current (DC) for use by electrical devices such as Atari computers
and peripherals.

In some cases, the entire conversion is done via an external "power supply"
that sits between the wall outlet and the electrical device.  Such power
supplies both transform the household power to a lower voltage, and they
also rectify the current from AC to DC.

In some cases, the external "power supply" is simply a transformer that lowers
the household voltage.  The lowered AC voltage is rectified to DC inside the
device.

In some cases, both the transformer and the rectifier are located inside the
computer or peripheral itself.  The device plugs directly into the wall
outlet, with no external "power supply" needed.

The INPUT of an external power supply will indicate:
  1) Input voltage in units of volts (110V for N.Am., 220V Euro, 240V UK)
  2) Input frequency in units of hertz (60Hz for N.Am., 50Hz Euro)

The OUTPUT of an external power supply will indicate:
  1) Output Voltage, in units of volts (V)
  2) Whether the output voltage is AC or DC
  3) one or sometimes both of:
    - Output Current, in units of amperes ("amps") (A) or milliamps (mA)
    - Output Power, in units of volt-amperes ("volt-amps")(VA) or watts (W)

An external power supply may also indicate a peak power rating.  The power
rating is the highest amount of power the unit can supply, according to the
manufacturer, but this is only for a very brief time.  The power rating may be
indicated in units of volt-amperes (VA) or in units of watts (W).  The power
supplies themselves usually indicate this rating near the "Input" label (in
order to distinguish this rating from the sustained power output.)  The
power ratings for Atari power supplies are given below as "Max:"

Higher-than-specified power and current capacities are entirely usable, and
often preferable because such supplies run cooler and last longer.

In practice the power units VA and W are used interchangeably, even though
they are not identical.

Direct Current (DC):
Power (in watts) = current (in amps) * voltage (in volts)

Alternating Current (AC):
Apparent Power (in voltamps) = current (in amps) * voltage (in volts)
Effective/True Power (in watts) = current (in amps) * voltage (in volts)
                                  * cosine(phase, or angle of lag)
cosine(phase) is known as the "power factor"

N O R T H   A M E R I C A   INPUT = 105-125 VAC 60Hz
====================================================
AC supplies (external transformers)

  9 VAC  4.5 VA  500 mA  Max:7.5va  Atari #CO61515(unit)/CO61516(unit)
    1010

  9 VAC  5.4 VA  (600 mA)  Max:12va  Atari#C062195(unit)
    1030

  9 VAC  15.3 VA  1.7 A  Max:18.5W  Power Adaptor
    Atari#CO14319(unit)/CA014748(box - indicates 9.5 VAC 1.7 A)
    400,800,822,850,1200XL,1010,1020
    NOTE: This was also original equipment for the 810 disk drive, but Atari
      later determined that the 810 required more power (21 W) for reliable
      operation.  This power supply is not recommended for disk drives.
    NOTE also that this power supply is only barely adequate for the
      400/800/1200XL computers: Atari eventually specified the power
      requirement for the 400/800 at 19 W.

  9 VAC  31 VA  3.4 A  Max:50W  Power Adaptor
    Atari#C017945(unit)/CA017964(box)
    http://www.computerhistory.org/collections/accession/102688424
    400,800,810,822,850,1200XL,1010,1020,1050,XF551

  9.5 VAC  4.2A  (39.9 VA)  Max:53W  Atari#CO61636 Power Adaptor
    1027

  20 VAC  330 mA  (6.6 VA)  Max:7W  Power Adaptor
    Atari#CO60479(unit)/CA060535(box?)
    835

  20 VAC  400 mA  (8 VA)  Max:15W
    Novation AC Adapter Model No 901017 / Atari#CA016751-01(box?)
    830.  Top: "ATARI" logo + "Use with 830 Modem Only"
    http://www.computerhistory.org/collections/accession/102662648
      NOTE: Both the 830 box and the 850 Operator's Manual indicate different
      specs from this: 24 VAC/150mA.  To date, no such power supply has
      turned up.

DC supplies (external adapters)

  5 V DC  1 A  (5 W)  Max:17W  Atari#CO70042
    65XE,XE game system
    Two versions, as described by B&C ComputerVisions, see:
    http://www.myatari.com/ebay/psxl.jpg
    Version #5(bottom center), the Mini, is the smallest at 2" X 3" & 2" high.
    It was shipped with most XE Game Systems.  Not as rugged as version #6.
    For continuous operation use #6 for a 1 Amp instead of #5.  17W rating.

    Version #6(bottom right), the Logo, is the same size as Ver #4,
    3" X 4 1/2" & 2 1/2" high but has an Atari Logo molded into the case.
    It was shipped with most 65XE computers and later XE Game Systems.
    Very reliable.  Works great in most applications.

  5 V DC  1.5 A  7.5 VA  Max:varies, 25W 30W 40W  Atari#C061982/CA024814
    600XL,800XL,65XE,130XE,XE Game System
    Four versions, as described by B&C ComputerVisions, see:
    http://www.myatari.com/ebay/psxl.jpg
    Version #1(upper left), the White Brick, has a white top and dark brown
    bottom,  4" X 8" & 2 1/2" high.  Version #1 was shipped with early
    600XL/800XL computers.  Very reliable.  Very Rare.  30W rating.

    Version #2(lower left), the Black Brick, is same shape and size as Version
    #1 but all black, 4" X 8" & 2 1/2" high.  Version #2 was shipped with
    later 600XL/800XL computers.  Very reliable.  Very Rare.

    Version #3(center top), the Ingot, is solid & all black,
    3 1/4" X 5" & 2 1/2" high.  It was shipped with most 600XL/800XL and some
    65/130XE computers.  If this version fails it can damage the computer if
    not turned off quickly.  Not recommended for unattended operations.  If
    hum bars are seen on the screen disconnect Version #3 power packs.
    40W rating.

    Version #4(top right), the Box, is slightly smaller than the Ver #3 at
    3" X 4 1/2" & 2 1/2" high.  It was shipped with most 130XE computers.
    Very reliable.  Getting hard to find.  We recommend this version for 130XE
    and 800XL computers.  25W rating.

  6 V DC  300 mA  (1.8 W)  Max:?  Atari#???????
    "410 P" (rare version of 410) (center positive)

  9 V DC  500 mA  (4.5 VA)  Power Adapter  (Max:various ratings 9W to 12W)
    Atari#CO16353(unit, newer)/CO10472(unit, older)/CX261(box)
    XEP80,SX212,2600,CX42 (center positive)

E U R O P E   INPUT = 216~264V 50Hz
===================================
AC supplies (external transformers)
  8.5 VAC  4.25 VA  (0.5 A)  Max:?  Input 240V 50 Hz  (UK)
    Atari#CO61516/34
    1010

  8.52 VAC  4.26 VA  (0.5 A)  Max:?  Atari#CO61516-13  (New Zealand)
    1010

  9.3 VAC  15.44 VA  (1,66 A)  Max:?  FW 6799/Atari#CA014748?(box?)
    400,800,822,850,1010,1020
  
  9.5 VAC  1.5 A  (14.25 VA)  Max:?  TaMOD M 5496  Input: 240V 50 Hz (UK)
    400,800,822,850,1010,1020  (shipped with UK PAL 400)

  9 VAC  3.4 A  27 VA  Max:0.037Kw    Input: 240V 50Hz (UK)
    Atari#CO60592-34(unit)/CA017964(box) Power Adaptor
    TM 7498 or SA 8547
    http://www.mr-atari.com/afbeeldingen/hardwarediv/adapterboxedxl.jpg
    400,800,810,822,850,1010,1020,1050,XF551

  9 VAC  3.0 A  (  VA)  Max:?   Input: ??   (Europe?)
    Atari#CO60592-11(unit)/CA017964?(box?)
    PL028 or DV-9034A UP
    400,800,810,822,850,1010,1020,1050,XF551

DC supplies (external adapters)
  5 V DC  1.5 A  (7.5 VA)  Max:0.11A  Input: 240V~50Hz (UK)
    Atari#CO61763-34
    600XL,800XL,65XE,130XE,800XE,XE Game System

  5 V DC  1.5 A  (7.5 W)  Max:varies 22VA 26VA  Input: 220V 50Hz
    Atari#CO61763-11
    600XL,800XL,65XE,130XE,800XE,XE Game System

  (5 V DC)  (1.7 A)  8.5 VA   Max:?     Input: 240V 50Hz   (UK)
    Atari#CO61605
    600XL,800XL,65XE,130XE,800XE,XE Game System

  5 V DC  1.8 A  (9.0 W)  Atari#CO61763-107  (Poland)
    600XL,800XL,65XE,130XE,800XE,XE Game System

  9 V DC  500 mA  4.5 VA  Max:9W   Input: 220V 50Hz  (Germany)
    Atari#CO18084-117 AC/DC Adaptor
    XEP80,SX212,2600,CX42 (center positive)

  9 V DC  500 mA  (4.5 VA)  Max:9W  Input: 240V 50Hz (UK)
    Atari#CO18084-309/CO18084-306?
    XEP80,SX212,2600,CX42 (center positive)

  9.5 V DC  650 mA  (6.2 VA)  Max:15W  Input: 220V 50 Hz  (France)
    Atari#C016507
    XEP80,SX212,2600,CX42 (center positive)

  I) 29 V DC  600 mA  (17.4 W)  Max: 38VA  Input 220V 50 Hz  (Germany)
  II) 8.6 V DC  1 A  (8.6 W)
    Atari#14750  Type: 102501
    1025(Euro).  This unique adapter has two separate power output cables that
    both plug into the European 1025 printer

M O R E  I N F O
================
These draw their power from the SIO +5 V:
  XM301 (60 mA),XC11,XC12,ICD P:R: Connection,Wizztronics MidiMax,R-Verter

Draws power from the 600XL PBI:
  1064

These have built-in power supplies (plug directly into the wall):
  410 (except "410P"),815,820,825,1025(non-Euro),1029,XMM801,XDM121

OTHER:

Indus GT
  11.5 V DC  1.95 A  (22.4 VA)  Max:33W  DataByte#DV-9319A
  Center positive
  This is identical to the Atari power supply for earlier 2-port 5200s:
     Atari#CO18187(unit, early version)/CA019141(box)
  What happens if power supplies for the Atari 1050 and Indus GT are mixed?
  Paul Alhart writes (20 Jan 2004):
     "The Indus requires DC, the 1050 uses AC. Plug an Indus
     supply into a 1050 and it will usually blow the rectifier diodes in the
     1050. Plug an Atari supply into an Indus and it will blow the fuse in
     the supply. It can damage the mother board as well."

Multi I/O (MIO), all versions, can use both AC and DC supplies, BUT:
     stick to voltages of at least 6.2-7.2 V.
     On 2003.09.01 James Bradford wrote: "Doesn't matter what polarity the
     centre is, the MIO has a fullwave bridge rectifier in it.
     AC would be better because the diodes would be used half the time."

Rana 1000: 9 VAC  3.4 A  (30.6 VA)

MPP1000C modem: 9 V DC  200 mA  (1.8 W)