Why doesn't the CX55 VCS cartridge adaptor work with 5200 video upgrades?

[+x=usr(1536)]

5 hours ago, AtariHobbyLover said:

Looking a bit more closely at your photo, the placement of the LED relative to the version of the cartridge that I have suggests some internal reworking:

 

Note how the LED is placed lower in the case, and the shell is a repurposed 5200 cartridge.  How recently did you purchase your Atarimax?  Mine's about 3 or 4 years old, for reference.

[Zonie]

On 5/1/2023 at 9:54 PM, x=usr(1536) said:

-SNIP-

 

With respect to point 2: the CX55 has the distinction of being the only 2600 derivative to have composite video output from the factory, in addition to composite being its only type of video output.  However, most decent-quality video upgrades require access to the LUM0 through LUM2 signals on the 2600's TIA chip, as well as its colour and sync signals.  In a stock system, these signals are combined to form composite video, which is then output to the RF modulator along with audio and everything makes its way to the TV from there.

 

 

Hmm... Wonder if anyone has added a power connector and AV outputs to one to use as a standalone 2600? Stick them on the bottom so they cannot be used when it is plugged into the console?

 

Regarding how to get it to work on an AV modded 5200, I would think a good solution would be to add an AV or composite switchbox to the back of the CX55, plug the 5200's output into one input, the CX55 into the other input, and connect the output to the TV. Clunky, but then the whole thing is clunky to begin with. The el-cheapo straight through board design which has the cart ports on the ends instead of, perhaps, the 5200 port being a right angle so the thing could sit flat on the top of the console.

 

Honestly, I never understood the stupid thing. If you already had a 2600 library, you also have a 2600. What was wrong with keeping it and having two consoles? Two people can play at the same time in two different rooms instead of only one if using an adapter. The only reason to sell/buy the adapter is to expand the 5200 library for folks that don't already have a 2600.

 

My two cents...

[alex_79]

18 minutes ago, Zonie said:

Wonder if anyone has added a power connector and AV outputs to one to use as a standalone 2600? Stick them on the bottom so they cannot be used when it is plugged into the console?

I've seen it done on a Coleco Expansion Module, which, just like the CX55, is a complete 2600 that only uses the Colecovision for power and the RF out, and it looks really cool as a standalone console:

 

 

Given its shape, the CX55 wouldn't look that nice, I guess.

[Zonie]

22 minutes ago, alex_79 said:

I've seen it done on a Coleco Expansion Module, which, just like the CX55, is a complete 2600 that only uses the Colecovision for power and the RF out, and it looks really cool as a standalone console:

 

 

Given its shape, the CX55 wouldn't look that nice, I guess.

Yeah, Basically a Gemini. I actually have two of expansion modules and may mod one this way just for grins. There was also an Intellivision one called a "System Changer". Probably also an entire 2600.

[+-^CrossBow^-]

1 hour ago, Zonie said:

Yeah, Basically a Gemini. I actually have two of expansion modules and may mod one this way just for grins. There was also an Intellivision one called a "System Changer". Probably also an entire 2600.

Yes... it works in the same manner as the others taking power from the console and the injecting its own video output to the external video line off the cartridge port that was added on the model 2 units. Model 1 units require modification to add this in not too differently from what it done on the 4-port 5200s.

 

[+x=usr(1536)]

3 hours ago, Zonie said:

Hmm... Wonder if anyone has added a power connector and AV outputs to one to use as a standalone 2600? Stick them on the bottom so they cannot be used when it is plugged into the console?

Sitting on my projects table is an unfinished adapter to do basically this.  Right now it consists of breadboard with a 5200 cartridge slot soldered to it; power and A/V outputs still need to be built.  There are many reasons for that, but the most recent one follows:

 

Based on what @AtariHobbyLover is saying about the composite output on the CX55, the audio is also mixed in with the video and the audio output pin on the cartridge port is unused.  This means either demuxing the combined composite and audio signal to get separate signals (with attendant degradation of both), or going back to square one in terms of bringing signals out independently of the cartridge slot.

 

Quite honestly, I'm low on motivation to see this through at this point.  It's just one of those things where sure, it can be done, but for the amount of effort involved and the end results that'll be achieved there are other things I'd rather put the time and effort into.  Might pick it up again at some future point, but for now it's on more or less permanent hold.

[+x=usr(1536)]

Memo to self: lift R14 in the CX55 to prevent audio mixing in with Composite; take audio off from same point.

 

Pin 30 on 5200 cartridge port (2-port) for audio in; pin is unused by CX55.