Right fire button not working

[ChunkyPanda03]

I picked up a CX-2600 from a garage sale and was eager to play and it worked perfectly until I had my friend play with me. This is when I found out that the right controller port's fire button didn't work. I was thinking it may be something with the 16 pin bug or the diodes and was wondering if I should order this kit to repair it.

[Jeremy Popp]

I picked up a CX-2600 from a garage sale and was eager to play and it worked perfectly until I had my friend play with me. This is when I found out that the right controller port's fire button didn't work. I was thinking it may be something with the 16 pin bug or the diodes and was wondering if I should order this kit to repair it.

 

My guess for a non-working fire button from easiest most common to worst would be:

Bad joystick (bad pcb or bad cable)

Bad controller port (broken or corroded pin)

Bad/Cold/Broken solder joint or trace related to controller port

Bad TIA CHIP

 

None of the above suggestions would be helped by that repair kit. Most of it comes down to diagnosing things, and swapping chips back and forth (if you have a spare 2600 and all chips are socketed, it would be pretty easy)

[ChunkyPanda03]

It isn't a bad controller, PCB, or sodder joint and I thought it may be a bad component on the board. My only problem is that I can't a blueprint or any diagram that I can trace and find the components that are part of the fire button mechanism.

[zylon]

4sw or 6sw? 6sw have a 4th IC (hex buffer 4013) that can fail along the trigger lines from TIA to controller port. It fails mostly 2 ways: always firing, never firing.

[ChunkyPanda03]

4sw or 6sw? 6sw have a 4th IC (hex buffer 4013) that can fail along the trigger lines from TIA to controller port. It fails mostly 2 ways: always firing, never firing.

ok great so I should start off with replacing the hex buffer first but is there any other components I should buy as well just to save some time

Edited October 24, 2018 by ChunkyPanda03

[zylon]

ok great so I should start off with replacing the hex buffer first but is there any other components I should buy as well just to save some time

 

TIA would be next likely suspect. It's good to install a socket for the hex buffer while you have it out. As long as you've ruled out any port issues or bent/broken pins, those are the two most common causes of trigger line problems. Personally, I'd change the buffer and see 1st. TIA costs a lot more.

[ChunkyPanda03]

Ok will do I'll follow up with the results.

[AtariLeaf]

I had an issue last year in a light sixer where the right joystick was always firing, even with no joystick plugged in. I had replaced the 4050 but that wasn't it. In my case it was a capacitor C237 which is connected to pin 6 which is the input trigger. At first I just desoldered one leg of that capacitor to take it out of the circuit and low and behold the auto firing ceased. After replacing that cap all was well.