Number Input issue- repair?

[Maxwell Zorin]

I have a refurb, controller and a 2nd controller that works relatively well and noticed the other day while playing Rescue on Fractulus for the first time that my Number 6 button did not work. I put in River raid and noticed that pressing the 3 button picks level 1, the 6 button picks level 4 and the 9 picks the 7. This is the case with both of the controllers, so I think it is not a controller issue, but a problem with the (super) system. Has any one had this issue and successfully fixed it?

 

Thanks in advance!

 

[zylon]

1st thing I'd suspect would be the port itself- solder joints, bent/broken pins in back, pins pushed inward.

The 2nd thing that would come to mind are the little multi-plexer ICs behind each controller port. They are an "off the shelf" item. You can see them pictured here, just ignore that large loose IC.

Edited February 12, 2018 by zylon

[bohoki]

verify button presses with galaxian

[Maxwell Zorin]

Thanks for the repies:

 

Bohoki- good suggestion, River Raid is good for testing the keypad. In fact, I used River Raid to test out the controller in the second port. As I suspected, the number inputs work correctly in the other port. Its too bad that you cant just play games as player 1 in the second port. I heard you could do that on the intellivision.

 

The most sophisticated repair i have ever performed is fixing jittery Atari 2600 paddles by disassembling and cleaning the contacts. I have never soldered and don't own a soldering iron. But it seems be a big plus to be handy at repairs if you own a 5200.

 

The way Zylon described it makes it sound like it is a pretty straightforward repair. Just open up the casing access the ports and solder the pins so they are straighted out?

 

However what confused me was if the pins were bad, wouldnt they just not fire? Why would they output the opposite number accross the keypad? does anyone know what that would indicate and if soldering would help that?

 

I wonder if i should just try to secure a new cheap 5200 on ebay from someone who has given up on it because their controllers dont work

[zylon]

The pins inside the controller port sometimes get pushed backwards out of the socket and wind up touching another pin. Think of them as "L" shaped. If the IC behind the port is bad, it's easy to replace, but does involve soldering on 2-port consoles. An easy test on a 4-port would be just swap the IC with one from port 3 or 4. CD4052BEXV

Edited February 13, 2018 by zylon