Atari 2600

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Chip Info

Original Revision

  • +5V Regulator: 7805
  • A200: MPU: CO10745 (6507, a variant of the 6502)
  • A201: TIA: CO10444 (Television Interface Adapter)
  • A202: RIOT: CO10750 (6532)
  • A203: 4050B: Video & Joystick Button (trigger) buffer


R14 - R16

  • A200: MPU: CO10745 (6507, a variant of the 6502)
  • A201: TIA: CO10444 (Television Interface Adapter)
  • A202: RIOT: CO10750 (6532)
  • A203: +5V Regulator: 7805
  • A205: 555


Schematics

From the service manual:


Service Manual


Capacitor Info & Refresh Kit Installation

"Total Refresh" kits available here

Electrolytic Capacitors

Early Revs

C201	4.7uF	35v
C214	4.7uF	35v
C243	2200uF	16v

NTSC Junior

C20	4.7uF	35v
C26	2200uF	16v
C27	4.7uF	35v
C29	4.7uF	35v
C37	4.7uF	35v

Styrene Capacitors

These two silver-colored styrene capacitors are next in line for failure, causing a loss of audio. Discussed in Tech Tip #2 in the service manual. These caps are non-polarized.

Early PCBs
C206	820pf	50v
C207	820pf	50v

Junior
C53	820pf	50v
C54	820pf	50v


Polyester Film Capacitors

Atari field change order 1A notes factory-installed underrated caps in these locations causing video quality issues. Covered again in Service Bulletin Febuary 17, 1982. Near voltage regulator. Non-polarized.

C241	.1uF	100v
C242	.1uF	100v


Other Parts included with the Refresh Kit

820 Ohm Resistor - Blanking resistor - (Tech Tip 4, 11/17/82)
Improves color. Incorporated on Rev 16 PCBs and above. Earlier PCBs should have an 820 Ohm resistor added to the solder side between pin 6 and pin 9 of A201 (TIA).
Zener Diode & 1uF axial capacitors for static protection (SB Feburay 18, 1982)
Solder yellow 1uF cap in parallel with Zener diodes & trim capacitor leads. The marked end of the diode connects to joystick connector J202 & J203 pin 6 (button) and other end to closest ground plane.
To quickly determine pin 6, continuity check between A203 pin 7 or pin 9 to each joystick port
If A203 not present, each pin 6 is connected to one side of either C216 and C217
7805 Voltage Regulator
Stock units were rated close to needed current and frequently fail.
Stainless screw & net
Some 7805 regulators are riveted to an external heatsink. This screw / nut combo replaces the rivet.
DC Jack
Frequently fail or become loose, dirty, damaged, etc. Sometimes the slightest tap will cause a reset.