Atari VCS 2600 Jr Composite Mods

[@JRussellProductions]

Can I put in a suggestion? I discovered this flaw with the PAL 2600 Junior consoles. You see the resistor that is traced to PIN6 on the TIA (the 10K ohm resistor that is colour ring coded Gold, Brown, Black and Orange) which is R31. Desolder those resistor joints to remove that 10K ohm resistor and replace it with a 3.3K Ohm resistor (which is colour coded Gold, Orange, Orange and Red ) as that will improve the picture quality and make the pixels more noticeable like the 6-switch and 4-switch Vadar consoles.. I done it with mine and it showed a dramatic improved quality. Hope that helps :)

[@juddery]

@J.Russell Production, I'm about to try to restore a 2600 Junior that is in bad shape and am glad to have come across your comment, so I can give it a go. That is assuming the unit can be made to work at all. I haven't actually tried using it yet as every connector, including the cartridge slot and joystick ports, are covered in corrosion and the shielding is super rusty, so I don't exactly have high hopes. I'm hoping to be surprised though.

[@bobsbarnworkshop]

If you look at pins 12 and 13 of the Stella chip, they are tied together but are actually stereo audio, so separate them and have stereo output!

[@vanhetgoor]

HSS stands for Höhe Swindigkeit Stahl. Zie Amerkans call it High Speed Steel, the initials stay the same, just like ABS. (also a German invention)

[@SparksNZeros]

in case you ever decide to do this mod again from my experience of doing a similar mod to a famicom, i used a 3mm headphone jack socket that was wired for 3 pole so you could get left and right audio and video from it. Since a lot of early home video cameras had the same style of output, 3mm to rca composite cables are still readily available. It's ideal for small cases and keeping things looking clean and tidy.

[@JanBeta]

That’s an excellent idea. Also handy for modding other systems in the future. Thanks!

[@AnotherUser1000]

Can I ask some questions? 1) Since the signals are initially RGB, why don' t you use them as they are and feed them directly to the TV, via the RGB input? The only thing you could need, is maybe some amplifying. 2) Why didn' t you cut the power line of the modulator, in order to cut the RF noise off and lower the power consumption a bit, as well? 3) You could also desolder the inner pin of the RF RCA jack on the PCB and solder the video output of your hack. 4) The best place to drill and put the audio out jack, would be right beside the RF out jack and also toward straight to the TV set, as the manufacturer intended from the beginning. Nice job, anyway!

[@JanBeta]

Thanks! Okay, I'll try to answer as good as I can. I think the last 3 questions are a matter of preference mostly. ;) 1) It doesn't output separate color signals. The color is a combined signal but there's separate luminance signals. The easiest signal to get out of it is composite. It's also possible to make an s-video adapter but not much more. -> atarihq.com/danb/tia.shtml 2) I like to keep things as original as possible and this way the modulator still works. It doesn't degrade the composite signal too much so I'm fine with that. 3) Yes. I did a similar (reversible) hack on my ZX Spectrum and it's a nice method. Would have to destroy the modulator though (see 2) 4) There's not much room there actually without removing parts of the modulator. The right hand side was the most convenient (and least destructive) place to add the connectors for me.

[@hyzenthlay7151]

If you know what channel you are going to be using on the RF line, then bridge that direct, and repurpose the channel selector switch on the left of the console to turn the power to the RF module on or off, that way you can have it turned off when using composite, and no power getting to the RF module, leaving less interference and power consumption.

[@jolesco]

Interesting hack. Even if the first one didn't work on that board rev. it's cool that you left it in. Some times one has to try different things before it will work.

[@JanBeta]

Thanks. I could have just bought a pre-made thing but I wanted to try doing it (and failing) myself. :)

[@waldevv]

I recently saw a 5.5" black and white portable CRT TV at a local auction and I just knew it would be a perfect match for the 2600 jr considering how tiny the console is. Definitely worth the 10€ I got the TV for but annoyingly it has only AV inputs and no RF and it's a lot newer than I expected so I'm probably just going to convert the jr to composite to make use of it. The TV has a connector for an external antenna so maybe there is some way to get RF to work through that but I need to investigate

[@lenmewes2895]

Does anyone know which resistors do what? I completed the mod & the video output & audio out are pretty clear, but on mine the black colors appear to me more grey than black. I assume that possibly using a different value for one of the resistors would remedy this problem?

[@CortinasAndClassics]

Hi, very informative video. Can you please tell me what is the variable resistor below the power switch?

[@JanBeta]

Oh, it's for adjusting the video output. Mostly the colors. No idea which value it is if that's what you're asking. I don't have a schematic on hand at the moment.

[@CortinasAndClassics]

Jan Beta thanks, I was cleaning mine and moved the dial by mistake. I think the mod is great but a little above my ability.

[@wolverine9632]

It sounds weird hearing it pronounced "two-thousand-six-hundred"

[@JanBeta]

Haha, yeah, that's what non native speakers do. I learned how to say it in the meantime. ;)

[@intel386DX]

You do not need the transistor portion .

[@valshaped]

R50 there seems pretty damn resistive

[@kduhtdkzrt]

Val Ba dumm tsss!

[@wolverine9632]

Thank you. I live in the states and need to do this for my PAL system so I can use it for testing purposes. I am writing my first 2600 game and want it to be NTSC/PAL compatible.

[@JanBeta]

Nice! Hope it works for you. There's a lot of ways to do this I think, mine is not necessarily the best of course. :)

[@tenminutetokyo2643]

Replace the 7805 with a Trasco TSR 1-2145 DC converter.

[@CB3ROB-CyberBunker]

it can't smell like 1977 or 1985 as that is the early 1990s model :P

[@Lilithe]

Well I found your mod but this one seems less invasive: atariage.com/howto/composite.html

[@mikegravgaard340]

HSS is High Speed Steel. Cobalt is best.

[@JanBeta]

Ah, thanks! I'll have to learn my drills better in the future. :)