Player 1 Paddle too Sensitive

[fan4899]

Hello all. I've recently been playing alot of paddle games and noticed something peculiar. On every game I've played so far, the player 1 paddle is almost as twice as sensitive as the player 2 paddle. Is this normal? Both sets of paddles I own have this same behavior.

[Thomas Jentzsch]

No, that's not normal. Maybe your console has a problem?

[fan4899]

5 minutes ago, Thomas Jentzsch said:

No, that's not normal. Maybe your console has a problem?

Thats what I'm thinking is the case. The paddles have the same sensitivity as one another when plugged into the second controller port. I'm not really sure what could be causing the issue though. I've taken the console apart and everything looks fine, both ports are identical and all of the solder joints look fine.

[Steve Guidi]

12 hours ago, fan4899 said:

Thats what I'm thinking is the case. The paddles have the same sensitivity as one another when plugged into the second controller port. I'm not really sure what could be causing the issue though. I've taken the console apart and everything looks fine, both ports are identical and all of the solder joints look fine.

The paddles are built with a 1M-Ohm potentiometer, which is given 5V from pin 7 in the controller.  The system detects the "resistance" by measuring the time taken to charge an internal capacitor.  If the capacitor is out of spec, then the charge time will vary and produce a different and incorrect reading of the controller's potentiometer.

 

I suspect this is the case since you've verified the correct behavior on the other joystick port, using the same controller. Here's a link to the schematics showing a .068uF capacitor used on the analog input pins (5,9 for paddle inputs).  Perhaps you can just replace the ones used on the misbehaving port.

 

https://www.atariage.com/2600/archives/schematics/Schematic_2600_Low.html

 

Edited June 26, 2021 by Steve Guidi