No power on my Atari 2600

badger9800 first you want to make sure that your power adapter works. Use a multimeter and check the output. you should get 9volts on that. If that works check the jack and make sure that it is properly working. Measure the voltage on the jack with the power supply plugged in. If you have power on the jack, you are having issues with the boards circuitry. POWER SUPPLY

The power supply is composed of a +5 voltage regulator, filter capacitors, and the power on/off switch. Unregulated DC is supplied to the board from the battery eliminator. A supply of +5 volts is routed through a filter circuit to the RF modulator. The motherboard also receives its power (+5 volts Vcc) from the switchboard via t h e same 12-conductor ribbon cable referenced above. So work from this and let us know what you get.