Atari Jr Part 2 - Or "How to kill a retro games console..."

So, my Atari Jr is working but is stuck on black and white. No amount of fiddling with the TV switch will change the monochrome output to colour.

Road Runner - but in black and white

Meep.

This may have been down to the rather 'clunky' composite mod that I installed. This consisted of several resistors and a capacitor, somewhat clumsily soldered to the board in various places. I was, frankly, amazed that I got anything output that a TV could understand.

Man, that is ugly.

To get around the somewhat amateur nature of my mod I ordered a deluxe composite mod kit from the rather nice chaps at The Future Was 8-Bit. This has a rather nice discrete circuit board that contains a simple circuit to split out the composite and audio signals. This deluxe version has a simple connector with four flying leads and a 3.5mm four pole jack that accepts a composite/audio cable to simplify connecting to a TV even more. Nice.

Lovely composite mod kit.

Sorry chaps - you're no longer required.

All that's required is a few components to be removed as per the full colour instruction leaflet and then the four cables installed in the indicated locations. Easy.

Nearly ready to go..

This I did, but to my disappointment the output remained firmly in monochrome. After examining the board I noticed that there were several long solder 'whiskers' on the end of the pins of the cartridge port on the motherboard. I simply tidied them up with a quick touch of the soldering iron on each pin.

And that killed the console. Dead.

If you turn on a working Atari Jr with no cartridge then you get a grey square with no sound in the middle of the screen. Well, it turns out that this is also what my Atari Jr decided it would do from that point on too, even with a cartridge installed. Dangnabit.

It's dead (again) Jim.

I have no idea what happened - and I remain open to other ideas - but I think that either I somehow managed to zap one of the chips with static (I have some carpet in the work area I'm in) or one of the chips was starting to die - hence the monochrome output - and it just so happened to finally die after I cleaned up the pins of the cartridge port. Or maybe the shorted cap I found caused some damage? Who knows.

Either way, it's dead.

Back to eBay where I managed to find another Atari Jr for less than the cost of one of the TIA chips. Go figure. But it was a typical 'unit only, untested, worked when I put it away' but for the price it was worth a gamble.  After a few days it arrived and, as luck would have it, it had the exact same revision of board... more or less. I won't dwell too much on this bit as I basically just took the board, cleaned it up and then applied the composite mod to it, and stuck it in my cleaned case.

Unit number 2 - note missing silver label

Difference 1 - small cap now has its
own place on the board

Difference 2 - small cap is in different
location 

Difference 3 - voltage regulator looks
like a 1A rather than 0.5A

I did briefly toy with the idea of de-soldering the chips to put in my original board but I was too concerned that, if they are fragile, I might destroy them and be back to square one.

So I temporarily attached the composite mod to the new board. And....

Let's try that again, shall we?

Colours, so many colours...

Success! So, all that's needed now is to carefully solder the mod in properly and put it all back together.

Wires fed through the handy hole in the board

Wires trimmed, soldered into place

and secured with hot glue (I'm not proud!)

The connector board gets heatshrunk (shrinked?)

Cable connected up

I decided that I would put the cable connection inside the case and leave the cables permanently connected. The cable just needed to be fed through the case. To give some strain relief I wrapped it around one of the screw pillars which seemed to hold quite firmly.

Cable hidden in case

Finally, the cable fits perfectly through the 'channel 3/4' selector hole. This is not used by UK models and so is empty anyway. Looks almost like it was made for it..

Cable exit.

 One final test, and we're done.

MEEP! MEEP! This time in colour. :)